Orthodontic treatment and associated devices, systems, and methods

ABSTRACT

Devices, systems, and methods for orthodontic treatment planning and orthodontic treatment are disclosed herein. Various embodiments of the present technology, for example, are directed to a method of obtaining data characterizing movements of a patient&#39;s teeth from original positions to desired, final positions. In some embodiments, the method can include identifying one or more components of the movements, evaluating the movements, and/or modifying the movements. A method in accordance with several embodiments of the present technology can comprise obtaining an orthodontic treatment plan, which can include one or more suggested interventions to accomplish the tooth movements, a design of such intervention(s), and/or other useful information regarding the orthodontic treatment. In some embodiments, a method of the present technology comprises evaluating an orthodontic treatment during and/or after implementation of the treatment, which can include obtaining data characterizing current positions of the patient&#39;s teeth. Based on the evaluation, the method can include obtaining another orthodontic treatment plan and movement data characterizing movements of a patient&#39;s teeth from their current positions to desired, final positions.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims the benefit of priority to InternationalPatent Application No. PCT/US21/30377, titled DENTAL APPLIANCES ANDASSOCIATED METHODS OF MANUFACTURING, filed May 1, 2021, and U.S.Provisional Patent Application No. 63/165,747, titled ORTHODONTICTREATMENT PLANNING AND ASSOCIATED DEVICES, SYSTEMS, AND METHODS, filedMar. 25, 2021, each of which is incorporated by reference herein in itsentirety.

The present application is related to the following applications, eachof which is incorporated by reference herein in its entirety: U.S.Provisional Patent Application No. 62/842,391, filed May 2, 2019; U.S.patent application Ser. No. 16/865,323, titled DENTAL APPLIANCES,SYSTEMS AND METHODS, filed May 2, 2020; International Patent ApplicationNo. PCT/US20/31211, titled DENTAL APPLIANCES, SYSTEMS AND METHODS, filedMay 2, 2020; U.S. Provisional Patent Application No. 62/956,290, filedJan. 1, 2020; U.S. patent application Ser. No. 15/929,443, titled DENTALAPPLIANCES AND ASSOCIATED SYSTEMS AND METHODS OF USE, filed May 2, 2020;U.S. patent application Ser. No. 15/929,444, titled DENTAL APPLIANCESAND ASSOCIATED SYSTEMS AND METHODS OF USE, filed May 2, 2020; U.S.Patent Application No. PCT/US20/70017, titled DENTAL APPLIANCES ANDASSOCIATED SYSTEMS AND METHODS OF USE, filed May 2, 2020; U.S. patentapplication Ser. No. 15/929,442, titled DENTAL APPLIANCES AND ASSOCIATEDMETHODS OF MANUFACTURING, filed May 2, 2020; International ApplicationNo. PCT/US20/70016, titled DENTAL APPLIANCES AND ASSOCIATED METHODS OFMANUFACTURING, filed May 2, 2020; U.S. Provisional Patent ApplicationNo. 62/704,545, titled DENTAL APPLIANCES AND ASSOCIATED SYSTEMS ANDMETHODS OF USE, filed May 15, 2020; U.S. patent application Ser. No.17/302,227, titled DENTAL APPLIANCES AND ASSOCIATED SYSTEMS AND METHODSOF USE, filed Apr. 27, 2021; International Patent Application No.PCT/US21/70469, titled DENTAL APPLIANCES AND ASSOCIATED SYSTEMS ANDMETHODS OF USE, filed Apr. 27, 2021; U.S. Provisional Patent ApplicationNo. 63/275,401, titled DENTAL APPLIANCES AND ASSOCIATED METHODS OFMANUFACTURING, filed concurrently herewith; and U.S. patent applicationSer. No. 17/518,547, titled ORTHODONTIC TREATMENT AND ASSOCIATEDDEVICES, SYSTEMS, AND METHODS, filed concurrently herewith.

TECHNICAL FIELD

The present technology relates to orthodontic treatment and associateddevices, systems, and methods.

BACKGROUND

A common objective in orthodontics is to move a patient's teeth topositions where the teeth function optimally and aesthetically. To movethe teeth, the orthodontist may begin by obtaining multiple scans and/orimpressions of the patient's teeth to determine a series of correctivepaths between the initial positions of the teeth and the desired endingpositions. The orthodontist then fits the patient to one of two mainappliance types: braces or aligners.

Traditional braces consist of brackets and an archwire placed across afront side of the teeth, with elastic ties or ligature wires to securethe archwire to the brackets. In some cases self-ligating brackets maybe used in lieu of ties or wires. The shape and stiffness of thearchwire as well as the archwire-bracket interaction governs the forcesapplied to the teeth and thus the direction and degree of toothmovement. To exert a desired force on the teeth, the orthodontist oftenmanually bends the archwire. The orthodontist monitors the patient'sprogress through regular appointments, during which the orthodontistvisually assesses the progress of the treatment and makes manualadjustments to the archwire (such as new bends) and/or replaces orrepositions brackets. The adjustment process is both time consuming andtedious for the patient and more often than not results in patientdiscomfort for several days following the appointment. Moreover, bracesare not aesthetically pleasing and make brushing, flossing, and otherdental hygiene procedures difficult.

Aligners comprise clear, removable, polymeric shells having cavitiesshaped to receive and reposition teeth to produce a final tootharrangement. Aligners offer patients significantly improved aestheticsover braces. Aligners do not require the orthodontists to bend wires orreposition brackets and are generally more comfortable than braces.However, unlike braces, aligners cannot effectively treat allmalocclusions. Certain tooth repositioning steps, such as extrusion,translation, and certain rotations, can be difficult or impossible toachieve with aligners. Moreover, because the aligners are removable,success of treatment is highly dependent on patient compliance, whichcan be unpredictable and inconsistent.

Lingual braces are an alternative to aligners and traditional (buccal)braces and have been gaining popularity in recent years. Two examples ofexisting lingual braces are the Incognito™ Appliance System (3M UnitedStates) and INBRACE® (Swift Health Systems, Irvine, Calif., USA), eachof which consists of brackets and an archwire placed on the lingual, ortongue side, of the teeth. In contrast to traditional braces, lingualbraces are virtually invisible, and, unlike aligners, lingual braces arefixed to the patient's teeth and force compliance. These existinglingual technologies, however, also come with several disadvantages.Most notably, conventional lingual appliances still rely on abracket-archwire system to move the teeth, thus requiring multipleoffice visits and painful adjustments. For example, lingual technologieshave a relatively short inter-bracket distance, which generally makescompliance of the archwire stiffer. As a result, the overall lingualappliance is more sensitive to archwire adjustments and causes more painfor the patient. Moreover, the lingual surfaces of the appliance canirritate the tongue and impact speech, and make the appliance difficultto clean.

Therefore, a need exists for improved orthodontic appliances.

SUMMARY

The present technology is directed to orthodontic treatment andassociated devices, systems, and methods. For example, some aspects ofthe present technology are directed to methods of determining proposedmovements of the patient's teeth from original positions (e.g.,positions in which the teeth are maloccluded, misaligned, or otherwisein need of orthodontic correction) to final positions (e.g., positionsin which occlusion and/or alignment of the patient's teeth is improved).Various embodiments of the present technology are directed to novelmethods of evaluating the proposed movements of the patient's teeth. Forexample, a method in accordance with some embodiments of the presenttechnology includes decomposing overall movements of the patient's teethinto component movements. Such component movements can include movementsof all of a patient's teeth within one of the patient's dental archesaccording to the same transformation, movement of the patient's teethwithin one dental arch relative to one another, etc. Moreover, variousembodiments of the present technology include methods for modifying theproposed final positions and/or movements of the patient's teeth suchthat the orthodontic treatment is more realistic, more achievable,faster, less painful, and/or has another more desirable property.

Some aspects of the present technology are directed to methods ofobtaining an orthodontic treatment plan. The treatment plan can includefinal positions of the patient's teeth and/or movements of the patient'steeth. Additionally or alternatively, the treatment plan can include oneor more suggestions or indications of orthodontic interventions toaccomplish the tooth movements. In some embodiments, the treatment planincludes a design of an appliance configured to accomplish intraarchmovements. Various aspects of the present technology are directed tosuch appliance designs and methods of manufacturing. Moreover, thetreatment plan can include useful information such as an estimatedduration of the treatment, a complexity of the treatment, a number oforthodontic intervention required, etc. The treatment plan or anyportion thereof can be communicated to a human operator (e.g., anorthodontist, a patient, etc.). Once a treatment plan has beengenerated, reviewed, and/or modified, the treatment can be implemented(e.g., by installation of an appliance in the patient's mouth).

It can be useful to evaluate progress of an orthodontic treatment duringand/or after implementation of the orthodontic treatment. For example,an orthodontic treatment can be adjusted if it is determined during thetreatment that the patient's teeth are not moving as planned.Additionally or alternatively, if the treatment concludes and thepatient's teeth are still misaligned, maloccluded, or otherwise in needof further orthodontic correction, the treatment can be extended and/ora new treatment can be implemented. Various methods of the presenttechnology are directed to evaluating an orthodontic treatment andcomprise obtaining data characterizing current positions of thepatient's teeth during and/or after implementation of the orthodontictreatment and comparing the current positions to corresponding desiredpositions of the patient's teeth. In some embodiments, evaluating anorthodontic treatment comprises obtaining an overall displacement of atooth from its current position to its desired position and decomposingthe overall displacement into one or more component displacements, whichcan be compared to planned component displacements associated withmovement of the tooth from its original position to its desiredposition. Based on an evaluation of an orthodontic treatment, furtherrepositioning of the patient's teeth may be beneficial and/or necessaryto accomplish certain objectives of the treatment (e.g., improvedaesthetics, improved occlusion of the patient's teeth, etc.). Variousembodiments of the present technology are directed to methods ofobtaining a treatment plan and/or planned movements of a patient's teethfrom their current positions following a first orthodontic treatment todesired positions following an additional orthodontic treatment. In someembodiments, the desired positions of the patient's teeth after theadditional orthodontic treatment may be the same as the originallyplanned desired positions.

The subject technology is illustrated, for example, according to variousaspects described below, including with reference to FIGS. 1A-58.Various examples of aspects of the subject technology are described asnumbered clauses (1, 2, 3, etc.) for convenience. These are provided asexamples and do not limit the subject technology.

1. A method of obtaining an orthodontic treatment plan for a patient,the method comprising:

-   -   obtaining first data characterizing an original position of a        tooth of the patient;    -   obtaining second data characterizing a final position of the        patient's tooth;    -   based on the first and second data, determining a movement of        the patient's tooth from the original position to the final        position; and    -   decomposing the movement into an intraarch movement and an        interarch movement.

2. The method of Clause 1, wherein the intraarch movement comprises amovement of one or more of the patient's teeth in a first dental archrelative to the other ones of the patient's teeth in the first dentalarch.

3. The method of Clause 1 or Clause 2, wherein the interarch movementcomprises a movement of all of the patient's teeth in a first dentalarch relative to a second dental arch of the patient.

4. The method of any one of Clauses 1 to 3, wherein the interarchmovement is non-zero.

5. The method of any one of Clauses 1 to 4, further comprisingindicating a first orthodontic intervention to move the tooth accordingto the intraarch movement and a second orthodontic intervention to movethe tooth according to the interarch movement.

6. The method of any one of Clauses 1 to 5, wherein obtaining the seconddata comprises obtaining instructions from a clinician.

7. The method of Clause 6, wherein obtaining the first data comprisesobtaining intraoral scan data of the patient's teeth.

8. The method of any one of Clauses 1 to 7, wherein the intraarchmovement has six directions of movement.

9. The method of any one of Clauses 1 to 8, wherein the interarchmovement has six directions of movement.

10. The method of Clause 8 or Clause 9, wherein the six componentscomprise three translational directions of movement and three rotationaldirections of movement.

11. The method of any one of Clauses 1 to 10, further comprising, basedon the first and second data and the intraarch and interarch movements,determining third data characterizing an intermediate position of thepatient's tooth.

12. The method of Clause 11, wherein the intermediate position of thepatient's tooth corresponds to a position of the patient's tooth afterit has been moved from the original position according to the intraarchmovement.

13. The method of any one of Clauses 1 to 12, wherein decomposing themovement into an intraarch movement and an interarch movement comprisesapplying a transformation to the second data.

14. The method of Clause 13, wherein the transformation is rigid and/oraffine.

15. The method of any one of Clauses 11 to 14, wherein decomposing themovement into an intraarch movement and an interarch movement comprisesregistering the third data to the first data.

16. The method of any one of Clauses 5 to 15, further comprisingindicating a relative timing of implementation of the first orthodonticintervention with respect to the second orthodontic intervention.

17. A method of obtaining an orthodontic treatment plan comprising:

-   -   obtaining first data characterizing an original position of a        tooth in a dental arch of a patient;    -   obtaining second data characterizing a final position of the        patient's tooth;    -   based on the first and second data, determining movement data        characterizing a movement of the patient's tooth from the        original position to the final position; and    -   decomposing the movement data into first movement data and        second movement data,    -   wherein the first movement data characterizes a first component        of the movement achievable by a first orthodontic intervention,        and    -   wherein the second movement data characterizes a second        component of the movement achievable by a second orthodontic        intervention different than the first orthodontic intervention.

18. The method of Clause 17, wherein the first component of the movementcomprises a movement of the tooth with respect to other teeth in thedental arch of the patient.

19. The method of Clause 17 or Clause 18, wherein the dental arch is afirst dental arch, and wherein the second component of the movementcomprises a movement of the tooth with respect to a second dental archof the patient.

20. The method of any one of Clauses 17 to 19, wherein the firstorthodontic intervention comprises moving the tooth via an orthodonticdevice.

21. The method of any one of Clauses 17 to 20, wherein the secondorthodontic intervention comprises moving the tooth via orthognathicsurgery.

22. The method of any one of Clauses 17 to 21, wherein the secondorthodontic intervention comprises moving the tooth via an orthodonticdevice.

23. The method of any one of Clauses 20 to 22, wherein the orthodonticdevice comprises an orthodontic appliance configured to be secured toone or more of the patient's teeth and, once secured, apply forces tothe teeth to move the patient's teeth from an original position to afinal desired position.

24. The method of any one of Clauses 20 to 23, wherein the orthodonticdevice comprises an elastic, a temporary anchorage device, or aplatform.

25. A method for obtaining an orthodontic treatment plan comprising:

-   -   obtaining first data characterizing an initial position of a        tooth of a patient;    -   obtaining second data characterizing a preferred position of the        patient's tooth;    -   based on the first and second data, obtaining third data        characterizing a movement of the patient's tooth from the        initial position to the preferred position;    -   based on the first, second, and third data, identifying a        component of the third data, wherein the component of the third        data characterizes a portion of the movement of the patient's        tooth from the initial position to the preferred position such        that, after the patient's tooth is moved according to the        portion of the movement, the patient's tooth is located at an        intermediate position; and    -   suggesting an orthodontic treatment to move the tooth according        to the portion of the movement.

26. The method of Clause 25, wherein the portion of the movementcomprises an intraarch movement.

27. The method of Clause 25 or Clause 26, wherein the portion of themovement comprises interarch movement.

28. The method of any one of Clauses 25 to 27, wherein the portion ofthe movement comprises an entirety of the movement.

29. The method of any one of Clauses 25 to 28, further comprising, basedon the component of the third data, suggesting a parameter of theorthodontic treatment.

30. The method of any one of Clauses 25 to 29, wherein the orthodontictreatment comprises moving the patient's tooth with an orthodonticappliance according to the portion of the movement.

31. The method of Clause 29 or Clause 30, wherein the parametercomprises a stiffness of one or more portions of the appliance.

32. The method of any one of Clauses 29 to 31, wherein the parametercomprises a pre-set shape of one or more portions of the appliance.

33. The method of any one of Clauses 25 to 32, wherein the component isa first component characterizing a first portion of the movement and theorthodontic treatment is a first orthodontic treatment, the methodfurther comprising:

-   -   based on the first, second, and third data, identifying a second        component of the third data, wherein the second component of the        third data characterizes a second portion of the movement of the        patient's tooth from the initial position to the preferred        position; and    -   suggesting a second orthodontic treatment to move the tooth        according to the second portion of the movement.

34. The method of any one of Clauses 25 to 33, further comprisingcommunicating the orthodontic treatment plan to a human operator.

35. The method of Clause 34, wherein communicating the orthodontictreatment plan comprises visually displaying an animation of thepatient's tooth moving according to the portion of the movementcharacterized by the component of the third data.

36. The method of Clause 34 or Clause 35, wherein communicating theorthodontic treatment plan comprises visually displaying the initialposition, the preferred position, and/or the intermediate position.

37. One or more tangible, non-transitory computer-readable media storinginstructions that, when executed by one or more processors, cause theone or more processors to perform the method of any one of the Clausesherein.

38. A device comprising:

-   -   one or more processors; and    -   one or more tangible, non-transitory, computer-readable media        storing instructions that, when executed by the one or more        processors, cause the one or more processors to perform the        method of any one of the Clauses herein.

39. A method for designing an orthodontic appliance comprising:

-   -   obtaining an anatomy digital model representing a patient's        gingiva and teeth in an arrangement;    -   obtaining an appliance digital model representing an orthodontic        appliance design configured to use with the patient's teeth;    -   virtually deforming the appliance digital model into a        configuration in which the appliance is coupled to the patient's        teeth in the arrangement; and    -   evaluating the deformed configuration of the appliance digital        model.

40. The method of Clause 39, wherein the orthodontic appliance comprisesan appliance for repositioning one or more teeth of the patient.

41. The method of Clause 39 or Clause 40, wherein the orthodonticappliance comprises an anchor configured to be disposed adjacent thepatient's teeth and one or more arms extending away from the anchor,each of the one or more arms being configured to couple to a respectiveone or more of the patient's teeth.

42. The method of any one of Clauses 39 to 41, wherein the arrangementcomprises an original tooth arrangement.

43. The method of any one of Clauses 39 to 41, wherein the arrangementcomprises an intermediate tooth arrangement.

44. The method of any one of Clauses 39 to 41, wherein the arrangementcomprises a final tooth arrangement.

45. The method of any one of Clauses 39 to 44, wherein evaluating thedeformed configuration comprises determining whether the deformedappliance digital model impinges on the gingiva.

46. The method of any one of Clauses 39 to 45, wherein evaluating thedeformed configuration comprises evaluating relative positions of theappliance digital model and the gingiva.

47. The method of any one of Clauses 39 to 46, wherein evaluating thedeformed configuration comprises determining whether appliance is spacedapart from gingiva by greater than a predetermined threshold.

48. The method of any one of Clauses 39 to 47, wherein evaluating thedeformed configuration comprises determining whether any portion of thedeformed appliance digital model exceeds an elastic strain limit.

49. The method of any one of Clauses 39 to 48, wherein evaluating thedeformed configuration comprises determining a difference between aforce and/or moment applied to the teeth by the deformed appliance andan intended force and/or moment.

50. The method of Clause 49, wherein evaluating the deformedconfiguration comprises determining whether the difference between aforce and/or moment applied to the teeth by the deformed appliance andan intended force and/or moment exceeds a predetermined accuracy limit.

51. The method of any one of Clauses 39 to 50, wherein evaluating thedeformed configuration comprises determining if a force and/or momentapplied to the teeth by the deformed appliance exceeds a predeterminedmaximum force and/or moment.

52. The method of any one of Clauses 39 to 51, further comprising, basedon the evaluation, modifying the appliance digital model.

53. The method of Clause 52, wherein modifying the appliance digitalmodel comprises changing a configuration of at least one arm of theappliance digital model.

54. The method of Clause 52 or Clause 53, wherein modifying theappliance digital model comprises changing a geometry of a shape-setconfiguration for the appliance digital model.

55. The method of any one of Clauses 52 to 54, wherein modifying theappliance digital model comprises changing a configuration of an anchorof the appliance digital model.

56. The method of any one of Clauses 52 to 55, further comprising, aftermodifying the appliance digital model:

-   -   virtually deforming the modified appliance digital model into a        configuration in which the appliance is mated to the patient's        teeth; and    -   evaluating the deformed configuration of the modified appliance        digital model.

57. The method of any one of Clauses 39 to 56, wherein virtuallydeforming the appliance comprises performing a finite element analysis(FEA) using the appliance digital model.

58. A method for designing an orthodontic appliance for repositioning atooth of a patient, the orthodontic appliance having an anchor and anarm extending away from the anchor, the method comprising:

obtaining an anatomy digital model characterizing the patient's gingivaand teeth in an arrangement;

obtaining an appliance digital model characterizing an orthodonticappliance design; and

virtually deforming the appliance digital model based on the anatomydigital model.

59. The method of Clause 58, wherein virtually deforming the appliancemodel includes performing a finite element analysis (FEA).

60. The method of Clause 58 or Clause 59, further comprising obtainingan output from virtually deforming the appliance digital model based onthe anatomy digital model.

61. The method of Clause 60, wherein the output is a deformed appliancedigital model.

62. The method of Clause 60 or Clause 61, wherein the output comprises aposition of a first portion of the appliance digital model correspondingto the anchor of the orthodontic appliance relative to a position of thepatient's gingiva of the anatomy digital model.

63. The method of any one of Clauses 60 to 62, wherein the outputcomprises a measure of strain in the appliance digital model.

64. The method of any one of Clauses 60 to 63, further comprisingdetermining if the output is greater than a predetermined threshold.

65. The method of any one of Clauses 60 to 64, further comprisingdetermining if the output is less than a predetermined threshold.

66. The method of Clause 64 or Clause 65, wherein the predeterminedthreshold is an elastic strain limit.

67. The method of Clause 64 or Clause 65, wherein the predeterminedthreshold is a distance between the anatomy digital model and theappliance digital model.

68. The method of any one of Clauses 60 to 67, further comprisingmodifying the appliance digital model based on the output.

69. The method of any one of Clauses 60 to 68, further comprisingmodifying the anatomy digital model based on the output.

70. The method of any one of Clauses 58 to 69, wherein the arrangementis an original tooth arrangement.

71. The method of any one of Clauses 58 to 70, wherein the arrangementis a desired final tooth arrangement.

72. The method of any one of Clauses 58 to 71, wherein the arrangementis an intermediate tooth arrangement.

73. The method of any one of Clauses 58 to 72, wherein the appliancedigital model comprises a planar appliance digital model virtuallyrepresenting the orthodontic appliance in a substantially planar form.

74. The method of any one of Clauses 58 to 72, wherein the appliancedigital model comprises an intended appliance digital model virtuallyrepresenting a geometry of the orthodontic appliance in a shape-setform.

75. The method of any one of Clauses 58 to 72, wherein the appliancedigital model comprises a deformed intended appliance digital modelvirtually representing the geometry of the orthodontic appliance in aninstalled form.

76. A method for designing an orthodontic appliance for repositioning atooth of a patient, the orthodontic appliance having an anchor and atleast one arm extending away from the anchor, the method comprising:

-   -   obtaining a planar appliance digital model, the planar appliance        digital model virtually representing the appliance in a        substantially planar configuration;    -   obtaining a heat treatment fixture digital model, the heat        treatment fixture digital model characterizing a geometry of a        heat treatment fixture for shape-setting an appliance;    -   performing a first FEA using the planar appliance digital model        and the heat treatment fixture digital model;    -   obtaining an intended appliance digital model, the intended        appliance digital model virtually representing the appliance in        a three-dimensional configuration with a geometry based at least        in part on the heat treatment fixture digital model;    -   obtaining an original tooth arrangement (OTA) digital model, the        OTA digital model virtually representing a patient's teeth and        gingiva in an original arrangement;    -   performing a second FEA using the intended appliance digital        model and the OTA digital model; and    -   obtaining a deformed intended appliance digital model and an        analysis result.

77. The method of Clause 76, further comprising modifying the planarappliance digital model based on the analysis result.

78. The method of Clause 76 or Clause 77, further comprising modifyingthe heat treatment fixture digital model based on the analysis result.

79. The method of any one of Clauses 76 to 78, wherein performing thefirst FEA comprises:

-   -   discretizing at least one of the planar appliance digital model        and the heat treatment fixture digital model into a plurality of        finite elements and a plurality of nodes;    -   assigning material properties to at least one of the planar        appliance digital model and the heat treatment fixture digital        model;    -   defining a contact interaction between the planar appliance        digital model and the heat treatment fixture digital model;    -   assigning boundary conditions to at least one of the planar        appliance digital model and the heat treatment fixture digital        model;    -   defining an analysis parameter; and    -   running the FEA until an exit condition is reached.

80. The method of Clause 79, wherein assigning the boundary conditionsincludes assigning a non-zero displacement to an anchor portion of theplanar appliance digital model.

81. The method of Clause 79 or Clause 80, wherein assigning the boundaryconditions includes defining a relationship between an orientation of anarm of the planar appliance digital model and a base plane of a securingportion of the heat treatment fixture.

82. The method of Clause 81, wherein the arm of the planar appliancedigital model is tangent to the base plane of the securing portion ofthe heat treatment fixture.

83. The method of any one of Clauses 79 to 82, wherein assigning theboundary conditions includes assigning a displacement to an attachmentportion of the planar appliance digital model.

84. The method of Clause 83, wherein the displacement assigned to theattachment portion has a magnitude of zero.

85. The method of Clause 83, wherein the displacement assigned to theattachment portion has a non-zero magnitude.

86. The method of any one of Clauses 76 to 85, wherein performing thesecond FEA comprises:

-   -   discretizing at least one of the intended appliance digital        model and the OTA digital model into a plurality of finite        elements and a plurality of nodes;    -   assigning material properties to at least one of the intended        appliance digital model and the OTA digital model;    -   defining a contact interaction between the intended appliance        digital model and the OTA digital model;    -   assigning boundary conditions to at least one of the intended        appliance digital model and the OTA digital model;    -   defining an analysis parameter; and    -   running the FEA until an exit condition is reached.

87. A method for designing an orthodontic appliance for repositioning atooth of a patient, the orthodontic appliance having an anchor and anarm extending away from the anchor, the method comprising:

-   -   obtaining an OTA digital model of a patient's teeth and gingiva        in an original arrangement, the OTA digital model comprising        original position data of a tooth to be repositioned by the        orthodontic appliance when installed in the patient's mouth;    -   obtaining an FTA digital model characterizing the patient's        teeth and gingiva in a desired final arrangement, the FTA        digital model comprising final position data of the tooth;    -   determining displacement data characterizing a displacement        between the original position data of the tooth and the final        position data of the tooth;    -   obtaining a heat treatment fixture digital model based on the        FTA digital model;    -   obtaining a 3D template digital model based on the heat        treatment fixture digital model comprising a first portion        corresponding to the anchor of the orthodontic appliance in the        treatment configuration and a second portion corresponding to        the arm in the treatment configuration;    -   obtaining a planar template digital model, wherein the planar        template digital model is a substantially planar configuration        of the 3D template digital model;    -   obtaining a planar appliance digital model based on the planar        template digital model;    -   obtaining an intended appliance digital model, wherein the        intended appliance digital model characterizes the orthodontic        appliance in 3D configuration based on the heat treatment        fixture digital model; and    -   performing an FEA on the OTA and intended appliance digital        models to deform the intended appliance digital model based on        the displacement data.

88. The method of Clause 87, wherein obtaining the OTA digital modelincludes scanning the patient's teeth and gingiva.

89. The method of Clause 88, wherein scanning the patient's teeth andgingiva comprises optical scanning.

90. The method of Clause 88 or Clause 89, wherein scanning the patient'steeth and gingiva comprises computed tomography scanning.

91. The method of any one of Clauses 88 to 90, wherein scanning thepatient's teeth and gingiva comprises scanning an impression of thepatient's teeth and gingiva.

92. The method of any one of Clauses 87 to 91, further comprisingsegmenting the OTA digital model into a plurality of digital models ofeach tooth and at least one gingiva.

93. The method of any one of Clauses 87 to 92, further comprisingobtaining a securing member digital model representing a securingmember, the securing member configured to be adhered to a surface of thetooth and detachably couple with a portion of the orthodontic applianceto secure the orthodontic appliance to the tooth.

94. The method of Clause 93, further comprising obtaining an OTA withsecuring member digital model comprising a combination of the OTAdigital model and the securing member digital model, wherein thecombination is based on a desired placement of the securing member onthe patient's tooth when the orthodontic appliance is installed in thepatient's mouth during treatment.

95. The method of Clause 93 or Clause 94, further comprising obtainingan FTA with securing member digital model comprising a combination ofthe FTA digital model and the securing member digital model, wherein thecombination is based on a desired placement.

96. The method of Clause 94 or Clause 95, wherein the desired placementof the securing member is on a lingual surface of the patient's tooth.

97. The method of any one of Clauses 87 to 96, wherein the displacementdata comprises three translations and three rotations.

98. The method of any one of Clauses 87 to 97, wherein obtaining theintended appliance digital model comprises performing an FEA with theplanar appliance digital model and the heat treatment fixture digitalmodel.

99. The method of any one of Clauses 87 to 98, wherein the methodfurther comprises modifying the heat treatment fixture digital modelbased on the intended appliance digital model.

100. The method of Clause 97, wherein modifying the heat treatmentfixture digital model comprises defining a tangent relationship betweena gingival surface of the heat treatment fixture digital model and agingival-facing surface of the intended appliance digital model.

101. The method of any one of Clauses 99 to 100, further comprisingmanufacturing the planar template digital model.

102. The method of any one of Clauses 1 to 101, further comprisingmanufacturing the heat treatment fixture digital model.

103. The method of any one of Clauses 39 to 102, further comprisingmanufacturing the intended appliance digital model.

104. An orthodontic appliance manufactured in accordance with a methodof any one of the Clauses herein.

105. A fixture manufactured in accordance with a method of any one ofthe Clauses herein.

106. A tangible, non-transitory computer-readable medium configured tostore instructions that, when executed by one or more processors, causethe one or more processors to perform the method of any one of theClauses herein.

107. A device comprising:

-   -   one or more processors; and    -   a tangible, non-transitory computer-readable medium configured        to store instructions that, when executed by one or more        processors, cause the one or more processors to perform the        method of any one of the Clauses herein.

108. A method for determining an arrangement of an orthodontic device,the method comprising:

obtaining position data corresponding to an original tooth arrangement(OTA) of a patient;

obtaining position data corresponding to a first final tooth arrangement(FTA) of the patient, the first FTA differing from the OTA; and

determining position data corresponding to a second FTA, the second FTAbeing based at least in part on the first FTA and a predeterminedparameter, the second FTA differing from the first FTA,

-   -   wherein the second FTA can be used to form a fixture and/or an        orthodontic appliance, the appliance being configured to move        teeth of the patient from the OTA toward the first FTA or the        second FTA.

109. The method of Clause 108, further comprising manufacturing thefixture and/or the appliance according to at least the datacorresponding to the second FTA.

110. The method of Clause 108 or Clause 109, wherein the appliance isconfigured to move teeth of the patient generally from the OTA to thefirst FTA or to the second FTA.

111. The method of any one of Clause 108 to Clause 110, wherein theappliance is configured to have an arrangement generally correspondingto the second FTA in which the appliance is in a substantially unloadedstate.

112. The method of any one of Clauses 108 to 111, wherein the applianceis configured to have a first arrangement generally corresponding to thesecond FTA and a second arrangement generally corresponding to the OTA,the first arrangement corresponding to a substantially unloaded stateand the second arrangement corresponding to a loaded state.

113. The method of any one of Clauses 108 to 112, wherein thepredetermined parameter is associated with an expected movement of atleast one tooth of the patient after repositioning of the at least onetooth via the appliance to the second FTA.

114. The method of Clause 113, wherein the expected movement is in atleast one of the mesial-distal direction, lingual-facial direction, orocclusal-gingival direction. 115. The method of Clause 113 or 114,wherein the expected movement is a rotation about an axis defined by atleast one of the mesial-distal direction, lingual-facial direction, orocclusal-gingival direction.

116. The method of any one of Clauses 108 to 115, further comprisingmanufacturing the appliance such that the appliance in a substantiallyunloaded configuration generally corresponds to the second FTA, whereinthe first FTA corresponds to a predetermined desired position of thepatient's teeth.

117. The method of any one of Clauses 108 to 116, wherein the expectedrelapse corresponds to a positional difference between the first FTA andthe second FTA.

118. A method for determining an arrangement of an orthodontic device,the method comprising:

-   -   obtaining data corresponding to an original tooth arrangement        (OTA) of a patient; and    -   determining data corresponding to a final tooth arrangement        (FTA) based on the OTA and a predetermined parameter,    -   wherein the FTA can be used to form a fixture and/or an        orthodontic appliance, the appliance being configured to move a        patient's teeth from the OTA toward the FTA, and    -   wherein the predetermined parameter is based at least in part on        an expected relapse after repositioning the patient's teeth from        the OTA.

119. The method of Clause 118, wherein a minimum threshold force isneeded to move at least one tooth of the patient via the appliance, andwherein the predetermined parameter is associated with the minimumthreshold force.

120. The method of Clause 118 or Clause 119, wherein the appliance has aconfiguration in an unloaded state that generally corresponds to thesecond FTA.

121. The method of any one of Clauses 118 to 120, wherein the appliancehas a configuration in an unloaded state that generally corresponds tothe second FTA, and wherein the appliance is configured to move thepatient's teeth to the first FTA.

122. The method of any one of Clauses 118 to 121, wherein the appliancehas a configuration in an unloaded state that generally corresponds tothe second FTA, and wherein the appliance is configured to move thepatient's teeth to the first FTA and not to the second FTA.

123. The method of any one of Clauses 118 to 122, wherein:

-   -   a minimum threshold force is needed to move at least one tooth        of the patient via the appliance;    -   the predetermined parameter is associated with the minimum        threshold force; and    -   the appliance is configured to provide a non-zero force greater        than the minimum threshold along a path defined by at least the        OTA and the first FTA.

124. The method of any one of Clauses 118 to 123, wherein:

-   -   a minimum threshold force is needed to move at least one tooth        of the patient via the appliance;    -   the predetermined parameter is associated with the minimum        threshold force; and    -   the appliance, when in a configuration generally corresponding        to the first FTA, is configured to provide a non-zero force less        than the minimum threshold.

125. A method for determining an arrangement of an orthodontic device,the method comprising:

obtaining data corresponding to an original tooth arrangement (OTA) of apatient; and

determining data corresponding to a final tooth arrangement (FTA) basedon the OTA and a predetermined parameter,

-   -   wherein the FTA can be used to form a fixture and/or an        orthodontic appliance, the appliance being configured to move a        patient's teeth from the OTA toward the FTA, and    -   wherein a minimum threshold force is needed to move at least one        tooth of the patient via the appliance, and    -   wherein the predetermined parameter is associated with the        minimum threshold force.

126. The method of Clause 125, wherein the appliance is configured to becoupled to a securing member fixed to a patient's tooth, and wherein thepredetermined parameter is associated with an expected free play betweenthe appliance and the securing member.

127. The method of Clause 125 or Clause 126, wherein the applianceincludes an attachment portion configured to be coupled to a securingmember fixed to a patient's tooth, and wherein the predeterminedparameter is associated with an expected free play between theattachment portion and the securing member.

128. The method of any one of the Clauses herein, wherein:

-   -   the appliance includes an arm having an attachment portion        configured to be coupled to a securing member fixed to a        patient's tooth,    -   the predetermined parameter is associated with a free play        between the attachment portion and the securing member, the free        play corresponding to an angle of rotation in which the        attachment portion is able to rotate relative to the securing        member, and    -   the second FTA differs from the first FTA at least by the angle        of rotation.

129. The method of Clause 128, wherein the angle of rotation is in adirection corresponding to at least one of the mesial, distal, occlusal,gingival, facial, and/or lingual directions.

130. The method of any one of the Clauses herein, wherein:

-   -   the appliance includes an arm having an attachment portion        configured to be coupled to a securing member fixed to a        patient's tooth,    -   the predetermined parameter is associated with a free play        between the attachment portion and the securing member, the free        play corresponding to a dimension in which the attachment        portion is able to move relative to the securing member, and    -   the second FTA differs from the first FTA at least by the        dimension.

131. The method of Clause 130, wherein the dimension extends in adirection corresponding to at least one of the mesial-distal,occlusal-gingival, and/or facial-lingual directions.

132. The method of any one of the Clauses herein, wherein an arm of theappliance is configured to be coupled to a securing member fixed to apatient's tooth, and wherein the predetermined parameter is associatedwith an expected free play between the arm and the securing member.

133. A method for determining an arrangement of an orthodontic device,the method comprising:

obtaining data corresponding to an original tooth arrangement (OTA) of apatient; and

determining data corresponding to a final tooth arrangement (FTA) basedon the OTA and a predetermined parameter,

-   -   wherein the FTA can be used to form a fixture and/or an        orthodontic appliance, the appliance having a plurality of arms        that, when coupled to a patient's teeth via corresponding        securing members, are configured to be move a patient's teeth        from the OTA toward the FTA, and    -   wherein the predetermined parameter is based at least in part on        an expected free play between at least one of the arms and        corresponding securing member.

134. The method of any one of the Clauses herein, wherein thepredetermined parameter is associated with a positional differencebetween the first FTA and the second FTA.

135. The method of any one of the Clauses herein, wherein the applianceis configured to have a first arrangement corresponding to the first FTAand the fixture is configured to have a second configurationcorresponding to the second FTA, and wherein the predetermined parameteris associated with the difference between the first and secondarrangements.

136. The method of any one of the Clauses herein, further comprising:

-   -   manufacturing the fixture to have an arrangement corresponding        to the second FTA;    -   treating the appliance disposed over the fixture, thereby        causing the appliance to have an arrangement corresponding to        the first FTA.

137. The method of any one of the Clauses herein, further comprising:

-   -   manufacturing the fixture to have an arrangement corresponding        to the second FTA;    -   manufacturing the appliance to have a 2D configuration;    -   coupling the appliance over the fixture;    -   treating the appliance disposed over the fixture, thereby        causing the appliance to assume an arrangement corresponding to        the second FTA; and    -   decoupling the appliance from the fixture, thereby causing the        appliance to assume an arrangement corresponding to the first        FTA.

138. A method for determining an arrangement of an orthodontic device,the method comprising:

obtaining data corresponding to an original tooth arrangement (OTA) of apatient; and

determining data corresponding to a final tooth arrangement (FTA) basedon the OTA and a predetermined parameter,

-   -   wherein the FTA can be used to form a fixture and/or an        orthodontic appliance, the appliance being configured to move a        patient's teeth from the OTA toward the FTA, and    -   wherein the predetermined parameter is associated with an        expected plastic deformation threshold of the appliance.

139. The method of any one of the Clauses herein, wherein thepredetermined parameter is associated with a stress experienced by theappliance when in the OTA.

140. The method of any one of the Clauses herein, wherein thepredetermined parameter is associated with a material property of theappliance.

141. The method of any one of the Clauses herein, wherein the appliancecomprises a superelastic material, and wherein the predeterminedparameter is associated with plastic deformation associated with thesuperelastic material.

142. The method of any one of the Clauses herein, wherein the appliancecomprises nitinol, and wherein the predetermined parameter is associatedwith plastic deformation associated with nitinol.

143. The method of any one of the Clauses herein, wherein the appliancecomprises nitinol, and wherein the predetermined parameter is associatedwith hysteresis of nitinol.

144. The method of any one of the Clauses herein, wherein thepredetermined parameter is associated with a stress experienced by theappliance when in a configuration corresponding to at least one of theOTA or the FTA.

145. The method of any one of the Clauses herein, wherein:

-   -   the predetermined parameter is associated with an expected        plastic deformation threshold of the appliance,    -   the appliance includes an anchor portion and an arm extending        from the anchor portion, and the plastic deformation threshold        is associated with the arm of the appliance.

146. The method of any one of the Clauses herein, wherein:

-   -   the predetermined parameter is associated with an expected        plastic deformation threshold of the appliance,    -   the appliance includes an anchor portion and an arm extending        from the anchor portion, the arm including a biasing portion,        and    -   the plastic deformation threshold is associated with the biasing        portion of the appliance.

147. The method of any one of the Clauses herein, wherein the appliance,when coupled to the patient's teeth, is configured to transition from afirst configuration corresponding to the OTA, and wherein determiningthe data corresponding to the FTA comprises determining whether aportion of the appliance in the first configuration exceeds a yieldstrength of a material of the appliance.

148. The method of any one of the Clauses herein, wherein:

-   -   the appliance, when coupled to the patient's teeth, is        configured to transition from a first configuration        corresponding to the OTA, and    -   determining the data corresponding to the FTA comprises        determining whether a portion of the appliance in the first        configuration exceeds a yield strength of a material of the        appliance.

149. The method of any one of the Clauses herein, wherein the appliance,when coupled to the patient's teeth, is configured to transition from afirst configuration corresponding to the OTA to a second configurationcorresponding to the FTA, and wherein determining the data correspondingto the FTA comprises determining whether a portion of the appliance inthe first or second configuration exceeds a yield strength of a materialof the appliance.

150. A method for determining an arrangement of an orthodontic device,the method comprising:

obtaining data corresponding to an original tooth arrangement (OTA) of apatient; and

determining data corresponding to a final tooth arrangement (FTA) basedon the OTA and a predetermined parameter,

-   -   wherein the FTA can be used to form a fixture and/or an        orthodontic appliance, the appliance being configured to move        teeth of the patient from the OTA toward the FTA.

151. The method of any one of the Clauses herein, wherein thepredetermined parameter is that of any one of the clauses herein.

152. A method of fabricating an orthodontic appliance, the methodcomprising:

-   -   obtaining position data corresponding to an original tooth        arrangement (OTA) of a patient;    -   obtaining position data corresponding to a desired final tooth        arrangement (FTA) of the patient;    -   fabricating an orthodontic appliance that, when installed within        a mouth of the patient, is configured to urge teeth of the        patient from the OTA to the FTA, wherein, when the appliance is        coupled to the teeth of the patient in the FTA, the appliance        exerts a non-zero force on one or more teeth of the patient, the        non-zero force falling below a minimum threshold force.

153. A method of fabricating an orthodontic appliance, the methodcomprising:

-   -   obtaining position data corresponding to an original tooth        arrangement (OTA) of a patient;    -   obtaining position data corresponding to a desired final tooth        arrangement (FTA) of the patient;    -   fabricating an orthodontic appliance configured to move teeth of        the patient from the OTA toward the FTA; and shape-setting the        appliance by applying the appliance to a treatment fixture such        that the appliance assumes a first configuration, the fixture        having a shape that deviates from the FTA such that, after the        appliance is removed from the fixture, the appliance assumes a        second configuration in which at least a portion of the        appliance is deflected away from the first configuration.

154. A tangible, non-transitory computer-readable medium storinginstructions that, when executed by one or more processors, cause theone or more processors to perform a method of any one of the Clausesherein.

155. A device comprising:

-   -   one or more processors; and    -   a tangible, non-transitory computer-readable medium storing        instructions that, when executed by the one or more processors,        cause the one or more processors to perform the method of any        one of the Clauses herein.

156. An orthodontic appliance manufactured according to a method of anyone of the Clauses herein.

157. A heat treatment fixture manufactured according to a method of anyone of the Clauses herein.

158. A method for manufacturing an orthodontic appliance forrepositioning a tooth of a patient, the orthodontic appliance having ananchor and at least one arm extending away from the anchor, the armcomprising a proximal portion at the anchor and a distal portionconfigured to be secured to an orthodontic bracket, the methodcomprising:

-   -   obtaining first position data characterizing a first position of        the patient's tooth prior to repositioning of the tooth by the        appliance;    -   obtaining second position data characterizing a second position        of the patient's tooth after repositioning of the tooth by the        appliance;    -   obtaining third position data characterizing a desired position        of the patient's tooth after an anticipated movement of the        tooth after repositioning of the tooth by the appliance; and    -   forming a three-dimensional configuration of the appliance such        that the distal portion of the arm of the appliance is located        at the second position,    -   wherein the appliance is configured to reposition the tooth from        the first position to the second position such that, after the        tooth moves according to the anticipated movement, the tooth is        positioned at the desired position.

159. The method of Clause 158, wherein the appliance is configured toreposition the tooth from the first position to the second positionalong a path in a first direction.

160. The method of Clause 158 or Clause 159, wherein the anticipatedmovement of the tooth is along the path in a second direction oppositeof the first direction.

161. A method for designing an orthodontic appliance for repositioning atooth of a patient, the method comprising:

obtaining first position data characterizing an initial position of thepatient's tooth;

obtaining second position data characterizing an intended position ofthe patient's tooth;

obtaining deformation data characterizing an anticipated deformation ofthe appliance releasing the appliance from a shape-setting fixture; and

based on the first position data, the second position, and thedeformation data, obtaining appliance data characterizing athree-dimensional (3D) configuration of the appliance such that theappliance is configured to reposition the tooth from the initialposition to the intended position.

162. The method of Clause 161, wherein the anticipated deformation isdue to a superelastic property of the appliance.

163. The method of Clause 161 or Clause 162, wherein the orthodonticappliance has an anchor and at least one arm extending away from theanchor, the arm comprising a proximal portion at the anchor and a distalportion configured to be secured to an orthodontic bracket that isconfigured to be secured to the patient's tooth, and wherein a positionof the distal portion of the arm in the 3D configuration is differentthan the intended position of the tooth.

164. The method of any one of Clauses 161 to 163, wherein resiliencedata characterizes an anticipated deformation of the appliance aftersetting a shape of the appliance while the appliance is secured to theshape-setting fixture.

165. A method for designing an orthodontic appliance for repositioning atooth of a patient, the method comprising:

obtaining first position data characterizing an initial position of thepatient's tooth;

obtaining second position data characterizing an intended position ofthe patient's tooth;

obtaining appliance data characterizing a pre-installation configurationof the appliance;

obtaining deformation data characterizing an anticipated deformation ofthe appliance from the pre-installation configuration to an installedconfiguration; and

based on the first position data, the second position, and thedeformation data, obtaining modified appliance data characterizing amodified pre-installation configuration of the appliance.

166. The method of Clause 165, wherein the deformation datacharacterizes a stress and/or a strain in one or more portions of theappliance.

167. The method of Clause 165 or Clause 166, further comprisingdetermining whether plastic deformation is expected to occur at one ormore portions of the appliance due to the anticipated deformation of theappliance from the pre-installation configuration to the installedconfiguration.

168. The method of Clause 167, wherein determining whether plasticdeformation is expected to occur comprises comparing the deformationdata to at least one of a yield stress or a yield strain of a materialof the appliance.

169. The method of any one of Clauses 165 to 168, wherein the modifiedpre-installation configuration is a first modified pre-installationconfiguration, the method further comprising, after obtaining themodified appliance data:

-   -   obtaining second deformation data characterizing an anticipated        deformation of the appliance from the first modified        pre-installation configuration to an installed configuration;        and    -   based on the first position data, the second position, and the        deformation data, obtaining second modified appliance data        characterizing a second modified pre-installation configuration        of the appliance.

170. A method for designing an orthodontic appliance for repositioning atooth of a patient, the orthodontic appliance having an anchor and atleast one arm extending away from the anchor, the arm comprising aproximal portion at the anchor and a distal portion configured to bereceived within a securing portion of an orthodontic bracket, the methodcomprising:

-   -   obtaining first position data characterizing an initial position        of the patient's tooth prior to repositioning of the tooth by        the appliance;    -   obtaining second position data characterizing an intended        position of the patient's tooth after repositioning of the tooth        by the appliance;    -   obtaining arm data characterizing a dimension of the distal        portion of the arm of the appliance;    -   obtaining bracket data characterizing a dimension of the        securing portion of the orthodontic bracket;    -   obtain play data characterizing a difference between the arm        data and the bracket data;    -   based on the play data, obtaining force data characterizing an        anticipated force to be applied to the bracket by the appliance;        and    -   based on the force data, obtaining third position data        characterizing a passive position of the distal portion of the        arm of the appliance after the appliance has been shape-set, the        passive position being different than the intended position of        the tooth and/or the original position of the tooth.

171. The method of Clause 170, further comprising forming athree-dimensional configuration of the appliance such that the distalportion of the arm of the appliance is located at the second position.

172. The method of Clause 170 or 171, wherein obtaining the play datacomprises determining an anticipated maximum angular displacementbetween a plane of the distal portion of the arm and a plane of thesecuring portion of the bracket.

173. The method of any one of Clauses 170 to 172, wherein obtaining theforce data comprises determining an anticipated torque loss parameterassociated with a connection between the distal portion of the arm andthe securing portion of the bracket.

174. The method of any one of Clauses 170 to 173, wherein the arm datacharacterizes at least two of an occlusogingival dimension of the distalportion of the arm, a buccolingual dimension of the distal portion ofthe arm, or a mesiodistal dimension of the distal portion of the arm.

175. The method of any one of Clauses 170 to 174, wherein the bracketdata characterizes at least two of an occlusogingival dimension of thesecuring portion of the bracket, a buccolingual dimension of thesecuring portion of the bracket, or a mesiodistal dimension of thesecuring portion of the bracket.

176. The method of any one of Clauses 170 to 175, wherein obtaining theplay data comprises calculating an anticipated maximum distance betweenthe distal portion of the arm and the securing portion of the bracket.

177. A method for manufacturing an orthodontic appliance forrepositioning a tooth of a patient, the orthodontic appliance having ananchor and at least one arm extending away from the anchor, the armcomprising a proximal portion at the anchor and a distal portionconfigured to be secured to an orthodontic bracket that is secured tothe patient's tooth, the method comprising:

obtaining first position data characterizing an original position of thepatient's tooth prior to repositioning of the tooth by the appliance;

obtaining second position data characterizing an intended position ofthe patient's tooth after repositioning of the tooth by the appliance;and

setting a shape of the appliance such that, when the distal portion ofthe arm is secured to the bracket that is secured to the tooth and theappliance has repositioned the tooth to its intended position, theappliance applies a force to the tooth, the force having a magnitudegreater than a predetermined threshold.

178. The method of Clause 177, wherein the predetermined threshold isgreater than zero.

179. The method of Clause 177 or Clause 178, wherein the predeterminedthreshold is between about 5 grams and about 150 grams.

180. The method of any one of Clauses 177 to 179, wherein, after settinga shape of the appliance, the distal portion of the arm is located at apassive position, the passive position being different than the intendedposition of the tooth and/or the original position of the tooth.

181. The method of any one of Clauses 177 to 180, wherein thepredetermined threshold is unique to the tooth.

182. A method for designing an orthodontic appliance for repositioning atooth of a patient, the method comprising:

-   -   obtaining an appliance digital model characterizing the        orthodontic appliance in an initial configuration;    -   obtaining a fixture digital model characterizing a fixture for        setting a shape of the appliance; and    -   performing a finite element analysis (FEA) to virtually deform        the appliance digital model based on the fixture digital model.

183. The method of Clause 182, wherein the fixture digital modelcomprises:

-   -   a gingival portion having a shape substantially corresponding to        a surface of the patient's gingiva; and    -   at least one securing portion carried by the gingival portion        and configured to retain a portion of the appliance.

184. The method of Clause 182 or Clause 183, wherein performing the FEAcomprises causing at least one portion of the appliance digital model tosubstantially conform to the fixture digital model.

185. The method of any one of Clauses 182 to 184, wherein the appliancecomprises an anchor and an arm extending away from the anchor, the armcomprising a proximal portion at the anchor and a distal portionconfigured to be secured to an orthodontic bracket, and whereinperforming the FEA comprises positioning a distal portion of an arm ofthe appliance digital model at or within the securing portion of thefixture digital model.

186. The method of any one of Clauses 182 to 185, wherein the appliancecomprises an anchor and an arm extending away from the anchor, andwherein performing the FEA comprises applying a non-zero displacement toan anchor of the appliance digital model.

187. The method of any one of Clauses 182 to 186, wherein the applianceis substantially planar in the initial configuration.

188. A method for designing an orthodontic appliance for repositioning atooth of a patient, the method comprising:

-   -   obtaining an appliance digital model characterizing the        orthodontic appliance in a pre-installation configuration;    -   obtaining an anatomy digital model characterizing a patient's        teeth and gingiva in an original arrangement; and    -   performing an FEA to virtually deform the appliance digital        model based on the anatomy digital model.

189. The method of Clause 188, the appliance comprises an anchor and anarm extending away from the anchor, the arm comprising a proximalportion at the anchor and a distal portion configured to be secured toan orthodontic bracket, and wherein performing the FEA comprises causingthe distal portion of the arm to be positioned at or adjacent to one ofthe patient's teeth.

190. The method of Clause 188 or Clause 189, wherein the appliance has asubstantially three-dimensional (3D) shape in the pre-installationconfiguration.

191. The method any one of Clauses 188 to 190, further comprisingevaluating the deformed appliance digital model.

192. The method of Clause 191, wherein evaluating the deformed appliancedigital model comprises determining whether the deformed appliancedigital model impinges on the gingiva or is spaced apart from thegingiva by greater than a predetermined threshold.

193. The method of Clause 191 or Clause 192, wherein evaluating thedeformed configuration comprises determining whether any portion of thedeformed appliance digital model exceeds an elastic strain limit.

194. The method of any one of Clauses 191 to 193, wherein evaluating thedeformed configuration comprises determining a difference between aforce and/or moment applied to the teeth by the deformed appliance andan intended force and/or moment.

195. The method of any one of Clauses 191 to 194, further comprising,based on the evaluation, modifying the appliance digital model, whereinmodifying the appliance digital model comprises changing at least one ofa shape of an arm of the appliance, a shape of an anchor of theappliance, or a shape of the appliance in the pre-installationconfiguration.

196. A method for designing an orthodontic appliance for repositioning atooth of a patient, the method comprising:

-   -   obtaining a preliminary appliance digital model virtually        representing the appliance in a preliminary configuration;    -   obtaining a heat treatment fixture digital model, the heat        treatment fixture digital model characterizing a geometry of a        heat treatment fixture for shape-setting an appliance, wherein        the heat treatment fixture comprises a gingival surface having a        shape substantially corresponding to a shape of a gingival        surface of the patient and a securing portion configured to        releasably retain a portion of the appliance;    -   performing a first FEA to virtually deform the preliminary        appliance digital model based on the heat treatment fixture        digital model;    -   obtaining an intended appliance digital model virtually        representing the appliance in a three-dimensional configuration        with a geometry based at least in part on the heat treatment        fixture digital model;    -   obtaining an original tooth arrangement (OTA) digital model        virtually representing a patient's teeth and gingiva in an        original arrangement;    -   performing a second FEA to virtually deform the intended        appliance digital model based on the OTA digital model; and    -   obtaining a deformed intended appliance digital model and an        analysis result.

197. The method of Clause 196, wherein the appliance is substantiallyplanar in the preliminary configuration.

198. The method of Clause 196 or Clause 197, wherein performing thefirst FEA comprises:

-   -   discretizing at least one of the preliminary appliance digital        model and the heat treatment fixture digital model into a        plurality of finite elements and a plurality of nodes;    -   assigning material properties to at least one of the preliminary        appliance digital model and the heat treatment fixture digital        model;    -   defining a contact interaction between the preliminary appliance        digital model and the heat treatment fixture digital model;    -   assigning boundary conditions to at least one of the preliminary        appliance digital model and the heat treatment fixture digital        model;    -   defining an analysis parameter; and    -   running the FEA until an exit condition is reached.

199. The method of Clause 198, wherein assigning the boundary conditionsincludes at least one of assigning a non-zero displacement a portion ofthe planar appliance digital model or defining a relationship between anorientation of a portion of the planar appliance digital model and abase plane of a securing portion of the heat treatment fixture.

200. The method of any one of Clauses 196 to 199, wherein performing thesecond FEA comprises:

-   -   discretizing at least one of the intended appliance digital        model and the OTA digital model into a plurality of finite        elements and a plurality of nodes;    -   assigning material properties to at least one of the intended        appliance digital model and the OTA digital model;    -   defining a contact interaction between the intended appliance        digital model and the OTA digital model;    -   assigning boundary conditions to at least one of the intended        appliance digital model and the OTA digital model;    -   defining an analysis parameter; and    -   running the FEA until an exit condition is reached.

201. The method of Clause 200, wherein assigning the boundary conditionscomprises assigning a displacement to a portion of the intendedappliance digital model, the displacement based at least in part on amovement of the patient's tooth from the original arrangement to adesired final arrangement.

202. The method of any one of Clauses 196 to 201, wherein the analysisresult comprises at least one of a strain in the deformed intendedappliance digital model or a distance between the deformed intendedappliance digital model and the gingival surface of the patient.

203. The method of any one of Clauses 196 to 202 wherein the orthodonticappliance comprises an anchor and at least one arm extending away fromthe anchor, the arm comprising a proximal portion at the anchor and adistal portion configured to be secured to an orthodontic bracket.

204. The method of Clause 203, wherein performing the first FEA causesthe anchor of the appliance to be positioned at or adjacent to thegingival surface of the heat treatment fixture digital model.

205. The method of Clause 203 or Clause 204, wherein performing thesecond FEA causes the distal portion of the arm of the appliance to bepositioned at or adjacent to one of the patient's teeth.

206. A method for designing an orthodontic appliance for repositioning atooth of a patient, the method comprising:

-   -   obtaining an OTA digital model of a patient's teeth and gingiva        in an original arrangement, the OTA digital model comprising        original position data of a tooth to be repositioned by the        orthodontic appliance when installed in the patient's mouth;    -   obtaining an FTA digital model characterizing the patient's        teeth and gingiva in a desired final arrangement, the FTA        digital model comprising final position data of the tooth;    -   determining displacement data characterizing a displacement        between the original position data of the tooth and the final        position data of the tooth;    -   obtaining a heat treatment fixture digital model based on at        least one of the OTA digital model or the FTA digital model;    -   obtaining a 3D template digital model based on the heat        treatment fixture digital model; obtaining a planar template        digital model, wherein the planar template digital model is a        substantially planar configuration of the 3D template digital        model;    -   obtaining a planar appliance digital model based on the planar        template digital model; obtaining an intended appliance digital        model, wherein the intended appliance digital model        characterizes the orthodontic appliance in 3D configuration        based on the heat treatment fixture digital model;    -   performing an FEA on the OTA and intended appliance digital        models to deform the intended appliance digital model based on        the displacement data; and    -   evaluating an analysis result of the virtual deformation.

207. The method of Clause 206, wherein the displacement data comprisesthree translations and three rotations.

208. The method of Clause 206 or Clause 207, further comprisingmodifying the heat treatment fixture digital model based on the intendedappliance digital model.

209. The method of Clause 208, wherein modifying the heat treatmentfixture digital model comprises defining a tangent relationship betweena gingival surface of the heat treatment fixture digital model and agingival-facing surface of the intended appliance digital model.

210. The method of any one of Clauses 206 to 209, further comprisingmanufacturing at least one of the planar template digital model, theheat treatment fixture digital model, or the intended appliance digitalmodel.

211. The method of any one of Clauses 206 to 210, wherein theorthodontic appliance comprises an anchor and an arm extending away fromthe anchor, the arm comprising a proximal portion at the anchor and adistal portion configured to be secured to an orthodontic bracket.

212. A device for holding a planar configuration of an orthodonticappliance in a three-dimensional configuration while a heat treatment isapplied to the orthodontic appliance, the orthodontic appliancecomprising an attachment portion configured to be secured to anorthodontic bracket coupled to a tooth of a patient, the attachmentportion comprising a first region and a second region extending at anangle from the first region, the first region being occlusal to thesecond region, the device comprising:

-   -   a body portion comprising a surface having a shape corresponding        at least in part to a gingiva of a patient; and    -   a securing portion carried by the body portion and configured to        retain the attachment portion in a desired position during the        heat treatment, wherein the securing portion comprises a first        engagement surface, a second engagement surface, and a gap        between the first and second engagement surfaces, wherein the        gap is configured to receive the attachment portion such that a        first region of the attachment portion is positioned adjacent        the first engagement surface and a second region of the        attachment portion is positioned adjacent the second engagement        surface.

213. The device of Clause 212, wherein the securing portion isconfigured to limit motion of the attachment portion with respect to thesecuring portion along a first and second dimension of the securingportion.

214. The device of Clause 213, wherein the first engagement surface isconfigured to limit motion of the attachment portion along the firstdimension.

215. The device of Clause 213 or Clause 214, the second engagementsurface is configured to limit motion of the attachment portion alongthe second dimension.

216. The device of any one of Clauses 213 to 215, wherein the securingportion comprises a third engagement surface configured to limit motionof the attachment portion along the first and/or second dimension.

217. The device of any one of Clauses 212 to 216, wherein, when theattachment is retained by the securing portion at the desired position,the securing portion engages the attachment portion at two or morelocations.

218. The device of any one of Clauses 212 to 217, wherein, when theattachment portion is retained by the securing portion at the desiredposition, two or more edges of the attachment portion are free.

219. The device of any one of Clauses 212 to 218, wherein the securingportion is configured to retain an attachment portion having a widthwithin 0.1 mm and −0.1 mm of a nominal width of the attachment portion.

220. The device of any one of Clauses 212 to 219, wherein at least oneof the engagement surfaces comprises a raised region of the securingportion.

221. The device of any one of Clauses 212 to 220, wherein the attachmentportion is configured to be releasably secured to the securing portionsuch that motion of the attachment portion along a third dimension islimited.

222. The device of Clause 221, wherein the attachment portion isconfigured to be releasably secured to the securing portion of thedevice by wrapping an elongated member around the attachment portion andthe securing portion.

223. The device of Clause 222, wherein the elongated member is wrappedalong a generally diagonal path with respect to the first and/or seconddimensions.

224. The device of Clause 222 or Clause 223, wherein the securingportion includes a recess configured to receive at least a portion ofthe elongated member.

225. The device of any one of Clauses 212 to 224, wherein the desiredposition of the attachment portion is based at least in part on adesired position of a tooth of the patient.

226. The device of any one of Clauses 212 to 225, wherein, when theattachment portion is retained by the securing portion, one or moreportions of the appliance substantially conforms to the body portion ofthe device.

227. The device of any one of Clauses 213 to 226, wherein the attachmentportion of the appliance has a first projection extending along a firstdirection and a second projection extending along a second directiondisposed at an angle to the first direction, and wherein, when theattachment portion is retained by the securing portion at the desiredposition, the first projection engages the first engagement surface andthe second projection engages the second engagement surface.

228. The device of Clause 227, wherein the first engagement surface issubstantially parallel to the first direction.

229. The device of Clause 227 or Clause 228, wherein the secondengagement surface is substantially parallel to the second direction.

230. The device of any one of Clauses 227 to 229, wherein the first andsecond directions are substantially orthogonal.

231. The device of any one of Clauses 227 to 230, wherein, when theattachment portion is retained by the securing portion at the desiredposition, a first surface of the first projection engages the firstengagement surface and a second surface of the first projection is freeand a first surface of the second projection engages the secondengagement surface and a second surface of the second projection isfree.

232. A method of manufacturing an orthodontic appliance, the methodcomprising:

-   -   obtaining an orthodontic appliance in a substantially planar        configuration, the appliance comprising an attachment portion        including a first projection extending along a first direction        and a second projection extending along a second direction        disposed at an angle to the first direction;    -   obtaining a fixture comprising any of the devices of Clauses 212        to 231;    -   positioning the attachment portion at the desired position such        that the first projection engages the first engagement surface        and the second projection engages the second engagement surface;    -   securing the appliance to the fixture such that the attachment        portion is retained by the securing portion at the desired        position; and    -   forming a three-dimensional configuration of the appliance while        the appliance is secured to the fixture.

233. The method of Clause 232, wherein securing the appliance to thefixture comprises wrapping an elongated member about the securing memberand the attachment portion.

234. The method of Clause 233, wherein wrapping the elongated memberabout the securing member and the attachment portion comprises wrappingthe elongated member along a third direction that is disposed at anangle to the first and second directions.

235. The method of Clause 234, wherein the angle is about 45 degrees.

236. The method of any of Clauses 232 to 235, wherein forming thethree-dimensional configuration comprises heat-treating the applianceand fixture.

237. A device for forming a three-dimensional configuration of anorthodontic appliance comprising an attachment portion configured to besecured to an orthodontic bracket coupled to a tooth of a patient, theattachment portion comprising first and second regions extending along afirst direction and third and fourth regions extending along a seconddirection disposed at an angle to the first direction, wherein, when theappliance is installed in a mouth of a patient, the first region iscloser to the patient's gingiva than the second, third, and fourthregions and the third and fourth regions are closer to the patient'sgingiva than the second region, the device comprising:

-   -   a body portion comprising a surface corresponding at least in        part to a gingival surface of a patient; and    -   a securing portion carried by the body portion and configured to        retain the attachment portion of the orthodontic appliance at an        intended position, the securing portion comprising first and        second engagement surfaces that are substantially parallel to        the first direction and a third engagement surface that is        substantially parallel to the second direction,    -   wherein, when the attachment portion is retained by the securing        portion at the intended position, the first region engages the        first engagement surface, the second region engages the second        engagement surface, and at least one of the third region or the        fourth region engages the third engagement surface.

238. The device of Clause 237, wherein, when the attachment portion isretained by the securing portion at the intended position, a firstsurface of the first region engages the first engagement surface, afirst surface of the second region engages the second engagementsurface, and a first surface of at least one of the third region or thefourth region engages the third engagement surface.

239. The device of Clause 238, wherein, when the attachment portion isretained by the securing portion at the intended position, a secondsurface of the first region opposite the first surface along a width ofthe first region does not engage the securing portion.

240. The device of Clause 238 or Clause 239, wherein, when theattachment portion is retained by the securing portion at the intendedposition, a second surface of the second region opposite the firstsurface along a width of the second region does not engage the securingportion.

241. The device of any one of Clauses 238 to 240, wherein, when theattachment portion is retained by the securing portion at the intendedposition, a second surface of the third region opposite the firstsurface along a width of the third region does not engage the securingportion.

242. The device of any one of Clauses 238 to 241, wherein, when theattachment portion is retained by the securing portion at the intendedposition, a second surface of the fourth region opposite the firstsurface along a width of the fourth region does not engage the securingportion.

243. The device of any one of Clauses 237 to 242, wherein the thirdengagement surface is spaced apart from the first engagement surfacealong the second direction.

244. The device of any one of Clauses 237 to 243, wherein the thirdengagement surface is spaced apart from the second engagement surfacealong the second direction.

245. The device of any one of Clauses 237 to 244, wherein the firstengagement surface is spaced apart from the second engagement surfacealong the second direction.

246. The device of any one of Clauses 237 to 245, wherein the first andsecond directions are substantially orthogonal.

247. The device of any one of Clauses 237 to 246, wherein the intendedposition corresponds to or is derived from a desired position of a toothof the patient to be moved by the appliance.

248. The device of any one of Clauses 237 to 247, wherein when theattachment portion is retained by the securing portion, one or moreportions of the appliance substantially conforms to the body portion ofthe device.

249. A method of manufacturing an orthodontic appliance, the methodcomprising:

-   -   obtaining an orthodontic appliance in a substantially planar        configuration, the appliance an attachment portion configured to        be secured to an orthodontic bracket coupled to a tooth of a        patient, the attachment portion comprising first and second        regions extending along a first direction and third and fourth        regions extending along a second direction disposed at an angle        to the first direction, wherein, when the appliance is installed        in a mouth of a patient, the first region is closer to the        patient's gingiva than the second, third, and fourth regions and        the third and fourth regions are closer to the patient's gingiva        than the second region;    -   obtaining a fixture comprising any of the devices of Clauses 237        to 248;    -   positioning the attachment portion at the intended position such        that the first region engages the first engagement surface, the        second region engages the second engagement surface, and at        least one of the third region or the fourth region engages the        third engagement surface;    -   securing the appliance to the fixture such that the attachment        portion is retained by the securing portion at the intended        position; and    -   forming a three-dimensional configuration of the appliance while        the appliance is secured to the fixture.

250. The method of Clause 249, wherein, when the attachment portion ispositioned at the intended position, the third region or the fourthregion does not engage the first engagement surface, the secondengagement surface, or the third engagement surface.

251. The method of Clause 249 or Clause 250, wherein forming thethree-dimensional configuration of the appliance while the appliance issecured to the fixture comprises subjecting the appliance and thefixture to heat.

252. The method of Clause 251, wherein subjecting the appliance and theheat treatment fixture to heat comprises heating to at least 200 degreescentigrade.

253. The method of Clause 252, further comprising, after heating,cooling the appliance and the heat treatment fixture via liquid quenchor air cooling.

254. The method of any one of Clauses 249 to 253, further comprisingremoving the appliance from the fixture.

255. The method of Clause 254, wherein after removing the appliance fromthe fixture, the appliance maintains the three-dimensional configurationsuch that the attachment portion is at the intended position.

256. A device for forming a three-dimensional configuration of anorthodontic appliance comprising an attachment portion having a firstprojection extending along a first direction and a second projectionextending along a second direction disposed at an angle to the firstdirection, the device comprising:

-   -   a body portion comprising a surface corresponding at least in        part to a gingival surface of a patient; and    -   a securing portion carried by the body portion and configured to        retain the attachment portion of the arm of the orthodontic        appliance at an intended position, the securing portion        comprising a first channel extending along the first direction,        a second channel extending along the second direction,    -   wherein, when the attachment portion is retained by the securing        portion at the intended position, the first projection is        positioned within the first channel and the second projection is        positioned within the second channel such that a surface of the        first projection is substantially in contact with the first        channel and a surface of the second projection is substantially        in contact with the second channel.

257. The device of Clause 256, further comprising a third channelextending along a third direction disposed at an angle to the first andsecond directions, wherein the third channel is configured to receive anelongated member therein such that the elongated member releasablysecures the attachment portion of the arm to the securing portion of thedevice.

258. The device of Clause 256 or Clause 257, wherein the channel extendspartially into a thickness of the securing portion.

259. A method of manufacturing an orthodontic appliance, the methodcomprising:

-   -   obtaining an orthodontic appliance in a substantially planar        configuration, the appliance comprising an attachment portion        having a first projection extending along a first direction and        a second projection extending along a second direction disposed        at an angle to the first direction;    -   obtaining a fixture comprising any of the devices of Clauses 256        to 258;    -   positioning the attachment portion at the intended position such        that the first projection is positioned within the first channel        and the surface of the first projection is substantially in        contact with the first channel and such that the second        projection is positioned within the second channel and the        surface of the second projection is substantially in contact        with the second channel;    -   securing the appliance to the fixture such that the attachment        portion is retained by the securing portion at the intended        position; and    -   forming a three-dimensional configuration of the appliance while        the appliance is secured to the fixture.

260. The method of Clause 259, wherein, when the attachment portion ispositioned at the intended position, another surface of the firstprojection and another surface of the second projection do notsubstantially contact the fixture.

261. A device for forming a three-dimensional configuration of anorthodontic appliance comprising an attachment portion configured to besecured to an orthodontic bracket coupled to a tooth of a patient, thedevice comprising:

-   -   a body portion comprising a surface corresponding at least in        part to a gingival surface of a patient; and    -   a securing portion carried by the body portion and configured to        position the attachment portion of the orthodontic appliance at        an intended position, the securing portion comprising an        appliance-facing surface including one or more protrusions        extending from the appliance-facing surface away from the        securing member, wherein the one or more protrusions define at        least two engagement surfaces,    -   wherein, when the attachment portion is retained by the securing        portion at the intended position, the attachment portion        contacts the at least two engagement surfaces.

262. The device of Clause 261, wherein, when the attachment portion isretained by the securing portion at the intended position, at least oneregion of the attachment portion does not contact the at least twoengagement surfaces.

263. The device of Clause 261 or Clause 262, wherein the one or moreprotrusions comprise three protrusions.

264. The device of any one of Clauses 261 to 263, wherein the one ormore protrusions define three engagement surfaces.

265. The device of any one of the preceding Clauses, wherein the devicecomprises a metal.

266. The device of any one of the preceding Clauses, wherein the deviceis formed by additive manufacturing.

267. The device of any one of the preceding Clauses, wherein the deviceis formed by investment casting.

268. The device of any one of the preceding Clauses, wherein the bodyportion is monolithic with the securing portion.

269. The device of any one of the preceding Clauses, further comprisingan opening extending therethrough, wherein the opening is configured toreceive a fastener therein.

270. The device of any one of the preceding Clauses, wherein theelongated member is a ligature wire.

271. The device of any one of the preceding Clauses, wherein theappliance comprises an anchor configured be positioned adjacent to andextend along the patient's teeth.

272. The device of any one of the preceding Clauses, wherein theappliance comprises an arm extending from a first end positioned at ananchor to a free second end, wherein the free second end includes theattachment portion.

273. The device of any one of the preceding Clauses, wherein the surfaceof the body corresponds at least in part to a gingival surface of apatient when the patient's teeth are in an original arrangement.

274. The device of any one of the preceding Clauses, wherein the surfaceof the body corresponds at least in part to a gingival surface of apatient when the patient's teeth are in a final arrangement.

275. The device of any one of the preceding Clauses, wherein, when theattachment portion is retained by the securing portion at the intendedposition, the anchor substantially conforms to the body portion.

276. A method for determining an orthodontic treatment plan for moving aplurality of teeth disposed in one of a patient's jaws, the methodcomprising:

-   -   obtaining first data characterizing original positions of the        teeth;    -   obtaining second data characterizing final positions of the        teeth;    -   for each tooth, determining a displacement between the        corresponding original position and the corresponding final        position based on the first and second data; and    -   for each displacement,        -   determining a first portion of the displacement unique to            the tooth associated with the displacement, and        -   determining a second portion of the displacement shared by            all of the displacements.

277. The method of any one of the preceding Clauses, wherein thetreatment plan includes the use of a first orthodontic appliance and asecond orthodontic appliance, and wherein a) each of the first portionsof the displacements represent a movement of the corresponding toothcaused by a first orthodontic appliance, and b) each of the secondportions of the displacements represent a movement of the correspondingtooth caused by a second orthodontic appliance.

278. The method of any one of the preceding Clauses, further comprisingobtaining third data characterizing intermediate positions of the teeth,wherein the intermediate positions correspond to positions of the teethafter the teeth have been moved from their original positions accordingto the first portions of the displacements.

279. The method of any one of the preceding Clauses, further comprisingobtaining third data characterizing intermediate positions of the teeth,wherein the intermediate positions correspond to a rigid transformationof the teeth in the final positions.

280. The method of any one of the preceding Clauses, wherein a firsterror parameter characterizing a difference between the second data andthe first data is greater than a second error parameter characterizing adifference between the third data and the first data.

281. The method of any one of the preceding Clauses, wherein each of thefirst and second error parameters comprises a sum of a plurality ofdistance parameters, each distance parameter being associated with oneof the patient's teeth.

282. The method of any one of the preceding Clauses, wherein eachdistance parameter comprises a distance between a reference point on thepatient's tooth in one of the positions and a corresponding referencepoint on the tooth in another one of the positions.

283. The method of any one of the preceding Clauses, wherein thedistance comprises a Euclidian distance.

284. The method of any one of the preceding Clauses, wherein determiningthe first and second portions of the displacements comprises registeringthe second data to the first data.

285. The method of any one of the preceding Clauses, wherein the secondportions of the displacements are identical in six directions ofmovement, the six directions of movement comprising three translationaldirections of movement and three rotational directions of movement.

286. A tangible, non-transitory, computer-readable medium storinginstructions that, when executed by one or more processors of acomputing device, cause the one or more processors to performoperations, the operations comprising:

-   -   obtaining first data characterizing original positions of the        teeth;    -   obtaining second data characterizing final positions of the        teeth;    -   for each tooth, determining a displacement between the        corresponding original position and the corresponding final        position based on the first and second data; and    -   for each displacement,        -   determining a first portion of the displacement unique to            the tooth associated with the displacement, and        -   determining a second portion of the displacement shared by            all of the displacements.

287. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, further comprising obtaining third datacharacterizing intermediate positions of the teeth, wherein theintermediate positions correspond positions of the teeth after the teethhave been moved from their original positions according to the firstportions of the displacements.

288. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein determining the second portions of thedisplacements comprises determining a rigid transformation that alignsthe second data with the first data.

289. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein determining the first portions of thedisplacements comprises aligning the second data with the first dataaccording to the rigid transformation and determining a distance betweena first reference point of each of the teeth as characterized by thefirst data and a second corresponding reference point of each of theteeth as characterized by the aligned second data.

290. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein each displacement, each first portionof the displacement, and each second portion of the displacementcomprises a 4×4 transformation matrix.

291. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein the second portions of thedisplacements are identical in six directions of movement, the sixdirections of movement comprising three translational directions ofmovement and three rotational directions of movement.

292. A method comprising:

-   -   obtaining first data characterizing a first movement of a first        tooth of a patient from an original position to a desired final        position;    -   obtaining second data characterizing a second movement of a        second tooth of the patient from an original position to a        desired final position, wherein the second tooth is within the        same jaw of the patient as the first tooth; and    -   determining a first portion of the first movement that is        identical to a first portion of the second movement and a second        portion of the first movement that is unique from a second        portion of the second movement.

293. The method of any one of the preceding Clauses, further comprisingobtaining position data characterizing intermediate positions of thefirst tooth and the second tooth, wherein the intermediate position ofthe first tooth corresponds to a position of the first tooth after thefirst tooth is moved according to the first portion of the firstmovement and the intermediate position of the second tooth correspondsto a position of the second tooth after the second tooth is movedaccording to the first portion of the second movement.

294. The method of any one of the preceding Clauses, wherein the firstportions of the first and second movements are achievable by a firstorthodontic intervention and the second portions of the first and secondmovements are achievable by a second orthodontic intervention differentfrom the first orthodontic intervention.

295. The method of any one of the preceding Clauses, wherein the firstmovement comprises a sum of the first and second portions of the firstmovement.

296. The method of any one of the preceding Clauses, wherein the firstportions of the first and second movements each comprise a rigidtransformation defining translations along three axes and rotationsabout the three axes.

297. The method of any one of the preceding Clauses, wherein the secondportions of the first and second movements each comprise a uniquetransformation.

298. A tangible, non-transitory, computer-readable medium storinginstructions that, when executed by one or more processors of acomputing device, cause the one or more processors to performoperations, the operations comprising:

obtaining first data characterizing a first movement of a first tooth ofa patient from an original position to a desired final position;

obtaining second data characterizing a second movement of a second toothof the patient from an original position to a desired final position,wherein the second tooth is within the same jaw of the patient as thefirst tooth; and

-   -   determining a first portion of the first movement that is        identical to a first portion of the second movement and a second        portion of the first movement that is unique from a second        portion of the second movement.

299. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, the operations further comprising obtainingposition data characterizing intermediate positions of the first toothand the second tooth, wherein the intermediate position of the firsttooth corresponds to a position of the first tooth after the first toothis moved according to the first portion of the first movement and theintermediate position of the second tooth corresponds to a position ofthe second tooth after the second tooth is moved according to the firstportion of the second movement.

300. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein the first portions of the first andsecond movements are achievable by a first orthodontic intervention andthe second portions of the first and second movements are achievable bya second orthodontic intervention different from the first orthodonticintervention.

301. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein the first portions of the first andsecond movements each comprise a rigid transformation definingtranslations along three axes and rotations about the three axes.

302. A method for evaluating an orthodontic treatment plan for moving aplurality of teeth disposed in one of a patient's jaws, the methodcomprising:

obtaining first data characterizing original positions of the teeth;

obtaining second data characterizing desired final positions of theteeth; and

obtaining third data characterizing intermediate positions of the teeth,the intermediate positions corresponding to a rigid transformation ofthe teeth in the final positions.

303. A method of obtaining an orthodontic treatment plan comprising:

-   -   obtaining first data characterizing original positions of teeth        of a patient;    -   obtaining second data characterizing final positions of the        patient's teeth;    -   based on the first and second data, determining movement data        characterizing a movement of each of the patient's teeth from        the original position to the final position; and    -   decomposing the movement data into first movement data and        second movement data,    -   wherein the first movement data characterizes a first component        of the movement achievable by a first orthodontic intervention,        and    -   wherein the second movement data characterizes a second        component of the movement achievable by a second orthodontic        intervention different than the first orthodontic intervention.

304. The method of any one of the preceding Clauses, wherein at leastone of the first component of the movement or the second component ofthe movement comprises a movement of one of the patient's teeth in afirst dental arch of the patient relative to others of the patient'steeth in the first dental arch.

305. The method of any one of the preceding Clauses, wherein at leastone of the first component of the movement or the second component ofthe movement comprises a movement of all of the patient's teeth in afirst dental arch of the patient relative to all of the patient's teethin a second dental arch of the patient.

306. The method of any one of the preceding Clauses, wherein at leastone of the first component of the movement or the second component ofthe movement comprises a movement of all of the patient's teeth relativeto a skull of the patient.

307. The method of any one of the preceding Clauses, wherein at leastone of the first orthodontic intervention or the second orthodonticintervention comprises an orthodontic device.

308. The method of any one of the preceding Clauses, wherein theorthodontic device comprises an orthodontic appliance configured to besecured to the patient's teeth and, once secured, apply forces to theteeth to move the teeth from the original positions.

309. The method of any one of the preceding Clauses, wherein theorthodontic device comprises an orthodontic elastic, a temporaryanchorage device, or a platform.

310. The method of any one of the preceding Clauses, wherein at leastone of the first orthodontic intervention or the second orthodonticintervention comprises orthognathic surgery.

311. A method for obtaining a desired final arrangement of all of apatient's teeth disposed in both of the patient's jaws, the methodcomprising, the method comprising:

-   -   obtaining an OTA digital model characterizing an original        arrangement of the patient's teeth;    -   obtaining an FTA digital model characterizing a final        arrangement of the patient's teeth;    -   rigidly transforming the FTA digital model to align the FTA        digital model with the OTA digital model, thereby generating a        modified FTA digital model characterizing a modified final        arrangement of the patient's teeth; and    -   selecting the modified final arrangement as the desired final        arrangement.

312. The method of any one of the preceding Clauses, wherein a firsterror parameter characterizing a distance between corresponding teeth inthe final arrangement and the original arrangement is greater than asecond error parameter characterizing a distance between correspondingteeth in the modified final arrangement and the original arrangement.

313. A method for obtaining desired final positions of both of apatient's dental arches, the method comprising:

-   -   obtaining first data characterizing original positions of the        arches;    -   obtaining second data characterizing final positions of the        arches;    -   for each arch, determining a displacement between the        corresponding original position and the corresponding final        position based on the first and second data;    -   for each displacement,        -   determining a first portion of the displacement unique to            the arch associated with the displacement, and        -   determining a second portion of the displacement shared by            all of the displacements; and    -   obtaining third data characterizing modified final positions of        the arches corresponding to positions of the arches after being        moved from the original positions according to the first        portions of the displacements.

314. The method of any one of the preceding Clauses, further comprisingselecting the modified final positions of the arches as the desiredfinal positions of the arches.

315. A method of evaluating an orthodontic treatment, the methodcomprising:

-   -   obtaining first data characterizing original positions of a        patient's teeth;    -   obtaining second data characterizing planned positions of the        teeth;    -   for each tooth in one jaw of a patient, determining a planned        displacement between the corresponding original position and the        corresponding planned position based on the first and second        data;    -   for each planned displacement,        -   determining a first portion of the planned displacement            unique to the tooth associated with the planned            displacement, and        -   determining a second portion of the planned displacement            shared by all of the planned displacements;    -   obtaining third data characterizing actual positions of the        teeth after the teeth have been at least partially repositioned        by the orthodontic treatment;    -   for each tooth in the one jaw of the patient, determining a        residual displacement between the corresponding actual position        and the corresponding planned position based on the second and        third data;    -   for each residual displacement,        -   determining a first portion of the residual displacement            unique to the tooth associated with the residual            displacement, and        -   determining a second portion of the residual displacement            shared by all of the residual displacements;    -   comparing the first portion of the residual displacement to the        first portion of the planned displacement and comparing the        second portion of the residual displacement to the second        portion of the planned displacement; and    -   based at least in part on the comparison, indicating if further        orthodontic treatment is recommended.

316. The method of any one of the preceding Clauses, wherein theindication includes one or more suggested orthodontic interventions toaccomplish one or more portions of the residual displacements.

317. The method of any one of the preceding Clauses, wherein comparing acorresponding portion of the planned and residual displacementscomprises determining a remaining percentage of the correspondingportion of the planned displacement.

318. The method of any one of the preceding Clauses, wherein furtherorthodontic treatment is recommended if the percentage remaining of theplanned displacement for one of the teeth is greater than apredetermined threshold.

319. The method of any one of the preceding Clauses, wherein furtherorthodontic treatment is recommended if a magnitude of the residualdisplacement for one of the teeth is greater than a predeterminedthreshold.

320. The method of any one of the preceding Clauses, further comprising,before determining the residual displacements, registering the thirddata to the second data.

321. The method of any one of the preceding Clauses, wherein registeringthe third data to the second data comprises identifying a rigidtransformation that, when applied to the third data, reduces an errorparameter characterizing a difference between the third data and thesecond data.

322. The method of any one of the preceding Clauses, further comprising:

-   -   for each tooth in the one jaw of the patient, determining an        actual displacement between the corresponding original position        and the corresponding actual position based on the first and        third data;    -   for each actual displacement,        -   determining a first portion of the actual displacement            unique to the tooth associated with the actual displacement,            and        -   determining a second portion of the actual displacement            shared by all of the actual displacements.

323. A tangible, non-transitory, computer-readable medium storinginstructions that, when executed by one or more processors of acomputing device, cause the one or more processors to performoperations, the operations comprising:

obtaining first data characterizing original positions of a patient'steeth;

obtaining second data characterizing planned positions of the teeth;

for each tooth in one jaw of a patient, determining a planneddisplacement between the corresponding original position and thecorresponding planned position based on the first and second data;

-   -   for each planned displacement,        -   determining a first portion of the planned displacement            unique to the tooth associated with the planned            displacement, and        -   determining a second portion of the planned displacement            shared by all of the planned displacements;    -   obtaining third data characterizing actual positions of the        teeth after the teeth have been at least partially repositioned        by the orthodontic treatment;    -   for each tooth in the one jaw of the patient, determining a        residual displacement between the corresponding actual position        and the corresponding planned position based on the second and        third data;    -   for each residual displacement,        -   determining a first portion of the residual displacement            unique to the tooth associated with the residual            displacement, and        -   determining a second portion of the residual displacement            shared by all of the residual displacements;    -   comparing the first portion of the residual displacement to the        first portion of the planned displacement and comparing the        second portion of the residual displacement to the second        portion of the planned displacement; and    -   based at least in part on the comparison, indicating if further        orthodontic treatment is recommended.

324. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein the indication includes a suggestedorthodontic intervention to accomplish the residual displacements.

325. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein comparing a corresponding portion ofthe planned and residual displacements comprises determining a remainingpercentage of the corresponding portion of the planned displacement.

326. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, wherein further orthodontic treatment isrecommended if a magnitude of one or more portions of the residualdisplacement is greater than a predetermined threshold.

327. The tangible, non-transitory, computer-readable medium of any oneof the preceding Clauses, the operations further comprising, beforedetermining the residual displacements, registering the third data tothe second data.

328. A method of evaluating an orthodontic treatment, the methodcomprising:

-   -   obtaining first characterizing original positions of teeth of a        patient;    -   obtaining second data characterizing final positions of the        patient's teeth;    -   based on the first and second data, determining planned movement        data characterizing a planned movement of each of the patient's        teeth from the original position to the final position;    -   decomposing the planned movement data into first planned        movement data and second planned movement data, wherein the        first planned movement data characterizes a first component of        the planned movement achievable by a first orthodontic        intervention, and wherein the second planned movement data        characterizes a second component of the planned movement        achievable by a second orthodontic intervention;    -   obtaining third characterizing actual positions of the patient's        teeth after at least one of the first orthodontic intervention        or the second orthodontic intervention has been at least        partially implemented;    -   based on first and third data, determining actual movement data        characterizing an actual movement of each of the patient's teeth        from the original position to the actual position;    -   decomposing the actual movement data into first actual movement        data and second actual movement data, wherein the first actual        movement data characterizes a first component of the actual        movement achieved by the first orthodontic intervention, and        wherein the second actual movement data characterizes a second        component of the actual movement achieved by the second        orthodontic intervention;    -   comparing the first actual movement data to the first planned        movement data and comparing the second actual movement data to        the second planned movement data; and    -   based at least in part on the comparison, indicating whether        further orthodontic treatment is recommended.

329. The method of any one of the preceding Clauses, wherein comparingthe first actual movement data to the first planned movement datacomprises determining a percentage of the first portion of the plannedmovement that has been achieved by the first orthodontic intervention.

330. The method of any one of the preceding Clauses, wherein comparingthe second actual movement data to the second planned movement datacomprises determining a percentage of the second portion of the plannedmovement that has been achieved by the second orthodontic intervention.

331. The method of any one of the preceding Clauses, further comprising,based on the comparison, indicating a first orthodontic intervention toaccomplish the first component of the residual movement and indicating asecond orthodontic intervention to accomplish the second component ofthe residual movement data.

332. The method of any one of the preceding Clauses, wherein the firstorthodontic intervention is different from the second orthodonticintervention.

333. The method of any one of the preceding Clauses, wherein obtainingthe third data comprises obtaining image data characterizing thepatient's teeth after at least one of the first orthodontic interventionor the second orthodontic intervention has been at least partiallyimplemented.

334. A method of evaluating an orthodontic treatment, the methodcomprising:

-   -   obtaining an original tooth arrangement (OTA) digital model        characterizing original positions of a patient's teeth;    -   obtaining a final tooth arrangement (FTA) digital model        characterizing desired, final positions of the patient's teeth;    -   based on the OTA and FTA digital models, determining planned        displacement data characterizing a planned movement of each of        the patient's teeth from the original position to the final        position, wherein each planned movement has a first portion        unique to the tooth associated with the planned movement and a        second portion shared by all of the planned movements;    -   obtaining an actual tooth arrangement (ATA) digital model        characterizing actual positions of the patient's teeth;    -   registering the ATA digital model to the FTA digital model;    -   based on the registered ATA digital model and the FTA digital        model, determining residual movement data characterizing a        residual movement of each of the patient's teeth from the actual        position to the final position, wherein each residual movement        has a first portion unique to the tooth associated with the        residual movement and a second portion shared by all of the        residual movements;    -   comparing the first portions of the planned and residual        movements and comparing the second portions of the planned and        residual movements; and    -   based on the comparison, indicating whether further orthodontic        treatment is recommended.

335. The method of any one of the preceding Clauses, wherein at leastone of the OTA digital model, the FTA digital model, or the ATA digitalmodel is segmented and comprises a plurality of distinct tooth models.

336. The method of any one of the preceding Clauses, wherein obtainingthe ATA digital model comprises, for each of the teeth in the ATAdigital model, positioning a corresponding one of the distinct toothmodels from the OTA digital model or the FTA digital model at thecorresponding actual position of the tooth as characterized by the ATAdigital model.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present disclosure can be better understood withreference to the following drawings. The components in the drawings arenot necessarily to scale. Instead, emphasis is placed on illustratingclearly the principles of the present disclosure.

FIGS. 1A and 1B schematically illustrate directional references relativeto a patient's dentition.

FIG. 2A shows the schematic representation of an orthodontic applianceconfigured in accordance with the present technology installed in apatient's mouth adjacent the patient's dentition.

FIG. 2B is a schematic depiction of connection configuration optionsconfigured in accordance with embodiments of the present technology.

FIG. 2C is a schematic depiction of a portion of an appliance configuredin accordance with embodiments of the present technology.

FIGS. 3A and 3B are elevation views of an appliance configured inaccordance with several embodiments of the present technology installedin an upper and lower jaw of a patient's mouth with the patient's teethin an original tooth arrangement and a final tooth arrangement,respectively.

FIG. 3C depicts example stress-strain curves of nitinol and steel.

FIG. 4 is a schematic block diagram of a system for manufacturing anorthodontic appliance in accordance with the present technology.

FIG. 5 is a flow diagram of a process for designing an orthodonticappliance in accordance with the present technology.

FIG. 6 illustrates scanning a patient's teeth to obtain original tootharrangement data.

FIG. 7 illustrates an example of a digital model of a patient's teethand gingiva in an original tooth arrangement.

FIG. 8 illustrates an example of a digital model of a patient's teethand gingiva in a final tooth arrangement.

FIG. 9 illustrates an example of a digital model of a securing member.

FIG. 10 illustrates an example of a digital model of a patient's teethand gingiva and a plurality of securing members in an original tootharrangement.

FIG. 11 illustrates an example of a digital model of a patient's teethand gingiva and a plurality of securing members in a final tootharrangement.

FIG. 12 illustrates an example of a digital model of a shape formingfixture.

FIG. 13 illustrates an example of a digital model of a three-dimensionalappliance template that is based on the heat treatment fixture model.

FIG. 14 illustrates an example of a digital model of a substantiallyplanar appliance template.

FIG. 15 illustrates an example of a digital model of a substantiallyplanar appliance with unique arm geometry based on determineddisplacement of each tooth.

FIG. 16 illustrates a perspective view of an orthodontic appliance inaccordance with embodiments of the present technology.

FIG. 17 illustrates a perspective view of a shape forming fixture for anappliance in accordance with the present technology.

FIG. 18 is a perspective view of an orthodontic appliance fastened to aheat treatment fixture in accordance with the present technology.

FIG. 19 is a flow diagram of an example process for orthodonticallytreating a patient in accordance with the present technology.

FIG. 20 is a flow diagram of an example process for obtaining toothmovements in accordance with the present technology.

FIG. 21 illustrates movement data characterizing movements of apatient's teeth from original positions in an original arrangement tofinal positions in a final arrangement in accordance with the presenttechnology.

FIG. 22A illustrates a patient's teeth of one of a patient's dentalarches in an original arrangement.

FIG. 22B illustrates the teeth of FIG. 22A in a final arrangement afterthe teeth have been moved relative to one another in accordance with thepresent technology.

FIG. 22C illustrates a patient's dental arches in an originalarrangement.

FIG. 22D illustrates the dental arches of FIG. 22C in a finalarrangement after the arches have been moved relative to one another inaccordance with the present technology.

FIG. 22E illustrates a patient's dental arches.

FIG. 22F illustrates the dental arches of FIG. 22E after both of thearches have been moved relative to a reference point in accordance withthe present technology.

FIGS. 23A-23D are schematic diagrams of example orthodontic toothmovements in accordance with the present technology.

FIGS. 24A-24C are schematic diagrams of teeth of a patient in anoriginal arrangement, an intermediate arrangement, and a finalarrangement, respectively.

FIG. 25A depicts teeth of a patient who has a class II malocclusion.

FIGS. 25B and 25C illustrate example movements of teeth of the patientof FIG. 25A in accordance with the present technology.

FIG. 26 is a flow diagram of an example process for performing an archregistration in accordance with the present technology.

FIG. 27 is a flow diagram of an example process for performing an archregistration algorithm in accordance with the present technology.

FIGS. 28A-28C schematically illustrate a one-dimensional example ofperforming an arch registration in accordance with the presenttechnology.

FIGS. 29A-29C schematically illustrate a one-dimensional example ofperforming an arch registration in accordance with the presenttechnology.

FIG. 30 is a flow diagram of an example process for performing a toothregistration in accordance with the present technology.

FIG. 31 is a flow diagram of an example process for performing a toothregistration algorithm in accordance with the present technology.

FIGS. 32A-32E schematically illustrate a two-dimensional example ofperforming a tooth registration in accordance with the presenttechnology.

FIG. 33A is a perspective view of a heat treatment fixture in accordancewith the present technology.

FIGS. 33B and 33C are front and side views, respectively, of a securingportion of the heat treatment fixture shown in FIG. 33A in accordancewith the present technology.

FIG. 33D depicts an attachment portion of an orthodontic appliancesecured to the securing portion of the heat treatment fixture shown inFIGS. 33A-33C in accordance with the present technology.

FIG. 34A depicts an attachment portion of an orthodontic appliancesecured to a securing portion of a shape forming fixture in accordancewith the present technology.

FIG. 34B is a perspective view of the securing portion of FIG. 34A inaccordance with the present technology.

FIG. 35 is a flow diagram of an example process for determining a designof an orthodontic appliance.

FIG. 36 is a flow diagram of an example process for determining a designof an orthodontic appliance.

FIG. 37 illustrates an example of an intended appliance digital modelobtained by performing a finite element analysis with a planar appliancedigital model and a heat treatment fixture digital model.

FIG. 38 illustrates an example of a deformed intended appliance digitalmodel obtained by performing a finite element analysis with an intendedappliance digital model and an OTA digital model.

FIG. 39 illustrates an example of a result of a finite element analysis.

FIG. 40 illustrates another example of an analysis result.

FIG. 41 illustrates an example of results from iterative finite elementanalyses.

FIG. 42 is a plot showing the relationship between force applied to apatient's teeth and positioning of the patient's teeth.

FIG. 43 is a flow diagram of a method for determining data correspondingto an arrangement of an orthodontic device in accordance withembodiments of the present technology.

FIG. 44A is a perspective view of a securing member, FIG. 44B is aperspective view of a portion of an arm of an orthodontic appliancecoupled to the securing member shown in FIG. 44A, and FIG. 44C is anenlarged side view of the securing member and appliance shown in FIG.44B, in accordance with embodiments of the present technology.

FIG. 45A is a perspective view of a securing member, FIG. 45B is aperspective view of a portion of an arm of an orthodontic appliancecoupled to the securing member shown in FIG. 45A, and FIG. 45C is anenlarged side view of the securing member and appliance shown in FIG.45B, in accordance with embodiments of the present technology.

FIG. 46 is a flow diagram of a method for determining data correspondingto an arrangement of an orthodontic device, in accordance withembodiments of the present technology.

FIG. 47 is a flow diagram of a method for determining data correspondingto an arrangement of an orthodontic device, in accordance withembodiments of the present technology.

FIG. 48 is a side perspective view of an orthodontic appliance,configured in accordance with embodiments of the present technology, inaccordance with embodiments of the present technology.

FIG. 49 is a flow diagram of a method for determining data correspondingto an arrangement of an orthodontic device, in accordance withembodiments of the present technology.

FIG. 50 is a flow diagram of a method for determining data correspondingto an arrangement of an orthodontic device, in accordance withembodiments of the present technology.

FIG. 51 schematically illustrates overcorrection about various points ona tooth in accordance with embodiments of the present technology.

FIGS. 52A-52C depict a user interface illustrating various stages of ananimation configured to communicate an orthodontic treatment plan to ahuman operator in accordance with embodiments of the present technology.

FIG. 53 is a flow diagram of a method for evaluating an orthodontictreatment in accordance with embodiments of the present technology.

FIG. 54 is a flow diagram of a method for obtaining actual positiondata, actual movement data, and/or residual movement data in accordancewith embodiments of the present technology.

FIGS. 55A and 55B illustrates an example of a digital model of apatient's teeth in an actual tooth arrangement (e.g., an ATA digitalmodel) and an original tooth arrangement (e.g., an OTA digital model),respectively.

FIG. 55C illustrates two of the patient's teeth from the OTA digitalmodel shown in FIG. 55B aligned with a corresponding ones of thepatient's teeth of the ATA digital model shown in FIG. 55A.

FIG. 56A illustrates an example of a digital model of a patient's teethin an actual tooth arrangement and an example of a digital model of thepatient's teeth in a final tooth arrangement positioned in a digitalenvironment.

FIG. 56B illustrates the digital model of the patient's teeth in theactual tooth arrangement of FIG. 56A registered to the digital model ofthe patient's teeth in the final tooth arrangement of FIG. 56A in thedigital environment.

FIG. 57 illustrates a digital model of the patient's teeth in anoriginal arrangement, a digital model of the patient's teeth in a finalarrangement, and a digital model of the patient's teeth in an actualarrangement, and a digital model of the patient's teeth in anintermediate arrangement in a digital environment.

FIG. 58 is a flow diagram of an example process for designing anorthodontic treatment plan and/or system in accordance with embodimentsof the present technology.

DETAILED DESCRIPTION

The present technology relates to orthodontic treatment and associateddevices, systems, and methods. Some embodiments of the presenttechnology, for example, are directed to a method of obtaining plannedmovements of a patient's teeth from original positions in which theteeth are maloccluded, misaligned, or otherwise in need of orthodonticcorrection to desired positions in which the teeth are functionally andaesthetically improved. Various embodiments are directed to a method ofobtaining an orthodontic treatment plan in which orthodonticinterventions to accomplish the tooth movements are indicated. Someembodiments of the present technology are directed to orthodonticappliances and associated methods of manufacturing. A method of thepresent technology can comprise evaluating an orthodontic treatmentduring and/or after implementation of the treatment and, based on theevaluation, determining planned movements Specific details of severalembodiments of the technology are described below with reference toFIGS. 1A-58.

I. Definitions

FIGS. 1A and 1B schematically depict several directional terms relatedto a patient's dentition. Terms used herein to provide anatomicaldirection or orientation are intended to encompass differentorientations of the appliance as installed in the patient's mouth,regardless of whether the structure being described is shown installedin a mouth in the drawings. As illustrated in FIGS. 1A and 1B: “mesial”means in a direction toward the midline of the patient's face along thepatient's curved dental arch; “distal” means in a direction away fromthe midline of the patient's face along the patient's curved dentalarch; “occlusal” means in a direction toward the chewing surfaces of thepatient's teeth; “gingival” means in a direction toward the patient'sgums or gingiva; “facial” means in a direction toward the patient's lipsor cheeks (used interchangeably herein with “buccal” and “labial”);“lingual” means in a direction toward the patient's tongue; “anterior”means in a direction toward a front of the patient's body; and“posterior” means in a direction toward a back of the patient's body.

As used herein, the terms “proximal” and “distal” refer to a positionthat is closer and farther, respectively, from a given reference point.In many cases, the reference point is a certain connector, such as ananchor, and “proximal” and “distal” refer to a position that is closerand farther, respectively, from the reference connector along a linepassing through the centroid of the cross-section of the portion of theappliance branching from the reference connector.

As used herein, the terms “generally,” “substantially,” “about,” andsimilar terms are used as terms of approximation and not as terms ofdegree, and are intended to account for the inherent variations inmeasured or calculated values that would be recognized by those ofordinary skill in the art.

As used herein, the term “operator” refers to a clinician, practitioner,technician or any person or machine that designs and/or manufactures anorthodontic appliance or portion thereof, and/or facilitates the designand/or manufacture of the appliance or portion thereof, and/or anyperson or machine associated with installing the appliance in thepatient's mouth and/or any subsequent treatment of the patientassociated with the appliance.

As used herein, the term “force” refers to the magnitude and/ordirection of a force, a torque, or a combination thereof.

II. Overview of Orthodontic Appliances of the Present Technology

FIG. 2A is a schematic representation of an orthodontic appliance 100(or “appliance 100”) configured in accordance with embodiments of thepresent technology, shown positioned in a patient's mouth adjacent thepatient's teeth. FIG. 2B is an enlarged view of a portion of theappliance 100. The appliance 100 is configured to be installed within apatient's mouth to impart forces on one or more of the teeth toreposition all or some of the teeth. In some cases, the appliance 100may additionally or alternatively be configured to maintain a positionof one or more teeth. As shown schematically in FIGS. 2A and 2B, theappliance 100 can comprise a deformable member that includes one or moreattachment portions 140 (each represented schematically by a box), eachconfigured to be secured to a tooth surface directly or indirectly via asecuring member 160. The appliance 100 may further comprise one or moreconnectors 102 (also depicted schematically), each extending directlybetween attachment portions 140 (“first connectors 104”), between anattachment portion 140 and one or more other connectors 102 (“secondconnectors 106”), or between two or more other connectors 102 (“thirdconnectors 108”). Only two attachment portions 140 and two connectors102 are labeled in FIG. 2A for ease of illustration. As discussedherein, the number, configuration, and location of the connectors 102and attachment portions 140 may be selected to provide a desired forceon one or more of the teeth when the appliance 100 is installed.

The attachment portions 140 may be configured to be detachably coupledto a securing member 160 that is bonded, adhered, or otherwise securedto a surface of one of the teeth to be moved. In some embodiments, oneor more of the attachment portions 140 may be directly bonded, adhered,or otherwise secured to a corresponding tooth without a securing memberor other connection interface at the tooth. The attachment portions 140may also be referred to as “bracket connectors” or “male connectorelements” herein. The different attachment portions 140 of a givenappliance 100 may have the same or different shape, same or differentsize, and/or same or different configuration. The attachment portions140 may comprise any of the attachment portions, bracket connectors,and/or male connector elements disclosed in U.S. patent application Ser.No. 15/370,704 (Publ. No. 2017/0156823) filed Dec. 6, 2016, U.S. patentapplication Ser. No. 15/929,443 (Publ. No. 2021/0007830) filed May 2,2020, and U.S. patent application Ser. No. 15/929,444 (Publ. No.2020/0390524) filed May 2, 2020, which are incorporated by referenceherein in their entirety.

The appliance 100 may include any number of attachment portions 140suitable for securely attaching the appliance 100 to the patient's toothor teeth in order to achieve a desired movement. In some examples,multiple attachment portions 140 may be attached to a single tooth. Theappliance 100 may include an attachment portion for every tooth, fewerattachment portions than teeth, or more attachment portions 140 thanteeth. In these and other embodiments, the appliance 100 one or more ofthe attachment portions 140 may be configured to be coupled to one, two,three, four, five or more connectors 102.

As previously mentioned, the connectors 102 may comprise one or morefirst connectors 104 that extend directly between attachment portions140. The one or more first connectors 104 may extend along a generallymesiodistal dimension when the appliance 100 is installed in thepatient's mouth. In these and other embodiments, the appliance 100 mayinclude one or more first connectors 104 that extend along a generallyocclusogingival and/or buccolingual dimension when the appliance 100 isinstalled in the patient's mouth. In some embodiments, the appliance 100does not include any first connectors 104.

Additionally or alternatively, the connectors 102 may comprise one ormore second connectors 106 that extend between one or more attachmentportions 140 and one or more connectors 102. The one or more secondconnectors 106 can extend along a generally occlusogingival dimensionwhen the appliance 100 is installed in the patient's mouth. In these andother embodiments, the appliance 100 may include one or more secondconnectors 106 that extend along a generally mesiodistal and/orbuccolingual dimension when the appliance 100 is installed in thepatient's mouth. In some embodiments, the appliance 100 does not includeany second connectors 106. In such embodiments, the appliance 100 wouldonly include first connectors 104 extending between attachment portions140. A second connector 106 and the attachment portion 140 to which itis attached may comprise an “arm,” as used herein (such as arm 130 inFIGS. 2A and 2B). In some embodiments, multiple second connectors 106may extend from the same location along the appliance 100 to the sameattachment portion 140. In such cases, the multiple second connectors106 and the attachment portion 140 together comprise an “arm,” as usedherein. The use of two or more connectors to connect two points on theappliance 100 enables application of a greater force (relative to asingle connector connecting the same points) without increasing thestrain on the individual connectors. Such a configuration is especiallybeneficial given the spatial constraints of the fixed displacementtreatments herein.

Additionally or alternatively, the connectors 102 may comprise one ormore third connectors 108 that extend between two or more otherconnectors 102. The one or more third connectors 108 may extend along agenerally mesiodistal dimension when the appliance 100 is installed inthe patient's mouth. In these and other embodiments, the appliance 100may include one or more third connectors 108 that extend along agenerally occlusogingival and/or buccolingual dimension when theappliance 100 is installed in the patient's mouth. In some embodiments,the appliance 100 does not include any third connectors 108. One, some,or all of the third connectors 108 may be positioned gingival to one,some, or all of the first connectors 104. In some embodiments, theappliance 100 includes a single third connector 108 that extends alongat least two adjacent teeth and provides a common attachment for two ormore second connectors 106. In several embodiments, the appliance 100includes multiple non-contiguous third connectors 108, each extendingalong at least two adjacent teeth.

As shown in FIG. 2A, in some embodiments the appliance 100 may beconfigured such that all or a portion of one, some, or all of theconnectors 102 are disposed proximate the patient's gingiva when theappliance 100 is installed within the patient's mouth. For example, oneor more third connectors 108 may be configured such that all or aportion of the one or more third connectors 108 is positioned below thepatient's gum line and adjacent to but spaced apart from the gingiva. Inmany cases it may be beneficial to provide a small gap (e.g., 0.5 mm orless) between the third connector(s) 108 and the patient's gingiva, ascontact between the third connector(s) 108 (or any portion of theappliance 100) and the gingiva can cause irritation and patientdiscomfort. In some embodiments, all or a portion of the thirdconnector(s) 108 is configured to be in direct contact with the gingivawhen the appliance 100 is disposed in the patient's mouth. Additionallyor alternatively, all or a portion of one or more first connectors 104and/or second connectors 106 may be configured to be disposed proximatethe gingiva.

According to some embodiments, one or more connectors 102 may extendbetween an attachment portion 140 or connector 102 and a jointcomprising (a) two or more connectors 102, (b) two or more attachmentportions 140, or (c) at least one attachment portion 140 and at leastone connector 102. According to some embodiments, one or more connectors102 may extend between a first joint comprising (a) two or moreconnectors 102, (b) two or more attachment portions 140, or (c) at leastone attachment member and at least one connector 102, and a second jointcomprising (a) two or more connectors 102, (b) two or more attachmentportions 140, or (c) at least one attachment portion 140 and at leastone connector 102. An example of a connector 102 extending between (a) ajoint between a second and third connector 106, 108, and (b) a jointbetween a second connector 106 and an attachment portion 140 is depictedschematically and labeled 109 in FIG. 2B.

Each of the connectors 102 may be designed to have a desired stiffnessso that an individual connector 102 or combination of connectors 102imparts a desired force on one or more of the teeth. In many cases, theforce applied by a given connector 102 may be governed by Hooke's Law,or F=k×x, where F is the restoring force exerted by the connector 102, kis the stiffness coefficient of the connector 102, and x is thedisplacement. In the most basic example, if a connector 102 does notexist between two points on the appliance 100, then the stiffnesscoefficient along that path is zero and no forces are applied. In thepresent case, the individual connectors 102 of the present technologymay have varying non-zero stiffness coefficients. For example, one ormore of the connectors 102 may be rigid (i.e., the stiffness coefficientis infinite) such that the connector 102 will not flex or bend betweenits two end points. In some embodiments, one or more of the connectors102 may be “flexible” (i.e., the stiffness coefficient is non-zero andpositive) such that the connector 102 can deform to impart (or absorb) aforce on the associated tooth or teeth or other connector 102.

In some embodiments it may be beneficial to include one or more rigidconnectors between two or more teeth. A rigid connector 102 is sometimesreferred to herein as a “rigid bar” or an “anchor.” Each rigid connector102 may have sufficient rigidity to hold and maintain its shape andresist bending. The rigidity of the connector 102 can be achieved byselecting a particular shape, width, length, thickness, and/or material.Connectors 102 configured to be relatively rigid may be employed, forexample, when the tooth to be connected to the connector 102 or arm isnot to be moved (or moved by a limited amount) and can be used foranchorage. Molar teeth, for example, can provide good anchorage as molarteeth have larger roots than most teeth and thus require greater forcesto be moved. Moreover, anchoring one or more portions of the appliance100 to multiple teeth is more secure than anchoring to a single tooth.As another example, a rigid connection may be desired when moving agroup of teeth relative to one or more other teeth. Consider, forinstance, a case in which the patient has five teeth separated from asingle tooth by a gap, and the treatment plan is to close the gap. Thebest course of treatment is typically to move the one tooth towards thefive teeth, and not vice versa. In this case, it may be beneficial toprovide one or more rigid connectors between the five teeth. For all ofthe foregoing reasons and many others, the appliance 100 may include oneor more rigid first connectors 104, one or more rigid second connectors106, and/or one or more rigid third connectors 108.

In these and other embodiments, the appliance 100 may include one ormore flexible first connectors 104, one or more flexible secondconnectors 106, and/or one or more flexible third connectors 108. Eachflexible connector 102 may have a particular shape, width, thickness,length, material, and/or other parameters to provide a desired degree offlexibility. According to some embodiments of the present technology,the stiffness of a given connector 102 may be tuned via incorporation ofa one or more resiliently flexible biasing portions 150. As shownschematically in FIG. 2B, one, some, or all of the connectors 102 mayinclude one or more biasing portion 150, such as springs, eachconfigured to apply a customized force specific to the tooth to which itis attached.

As depicted in the schematic shown in FIG. 2C, the biasing portion(s)150 may extend along all or a portion of the longitudinal axis L1 of therespective connector 102 (only the longitudinal axis L1 for secondconnector 106 and the longitudinal axis L2 for third connector 108 islabeled in FIG. 2C). The direction and magnitude of the force and torqueapplied on a tooth by a biasing portion 150 depends, at least in part,on the shape, width, thickness, length, material, shape set conditions,and other parameters of the biasing portion 150. As such, one or moreaspects of the biasing portion 150 (including the aforementionedparameters) may be varied so that the corresponding arm 130, connector102, and/or biasing portion 150 produces a desired tooth movement whenthe appliance 100 is installed in the patient's mouth. Each arm 130and/or biasing portion 150 may be designed to move one or more teeth inone, two, or all three translational directions (i.e., mesiodistal,buccolingual, and occlusogingival) and/or in one, two, or all threerotational directions (i.e., buccolingual root torque, mesiodistalangulation and mesial out-in rotation).

The biasing portions 150 of the present technology can have any length,width, shape, and/or size sufficient to move the respective toothtowards a desired position. In some embodiments, one, some, or all ofthe connectors 102 may have one or more inflection points along arespective biasing portion 150. The connectors 102 and/or biasingportions 150 may have a serpentine configuration such that the connector102 and/or biasing portion 150 doubles back on itself at least one ormore times before extending towards the attachment portion 140. Forexample, in some embodiments the second connectors 106 double back onthemselves two times along the biasing portion 150, thereby formingfirst and second concave regions facing in generally differentdirections relative to one another (as an example, see FIG. 3B). Theopen loops or overlapping portions of the connector 102 corresponding tothe biasing portion 150 may be disposed on either side of a plane P(FIG. 2C) bisecting an overall width W (FIG. 2C) of the arm 130 and/orconnector 102 such that the extra length of the arm 130 and/or connector102 is accommodated by the space medial and/or distal to the arm 130and/or connector 102. This allows the arm 130 and/or connector 102 tohave a longer length (as compared to a linear arm) to accommodategreater tooth movement, despite the limited space in theocclusal-gingival or vertical dimension between any associated thirdconnector 108 and the location at which the arm 130 attaches to thetooth.

It will be appreciated that the biasing portion 150 may have othershapes or configurations. For example, in some embodiments the connector102 and/or biasing portion 150 may include one or more linear regionsthat zig-zag towards the attachment portion 140. One, some, or all ofthe connectors 102 and/or biasing portions 150 may have only linearsegments or regions, or may have a combination of curved and linearregions. In some embodiments, one, some, or all of the connectors 102and/or biasing portions 150 do not include any curved portions.

According to some examples, a single connector 102 may have multiplebiasing portions 150 in series along the longitudinal axis of therespective connector 102. In some embodiments, multiple connectors 102may extend between two points along the same or different paths. In suchembodiments, the different connectors 102 may have the same stiffness ordifferent stiffnesses.

In those embodiments where the appliance 100 has two or more connectors102 with biasing portions 150, some, none, or all of the connectors 102may have the same or different lengths, the same or different widths,the same or different thicknesses, the same or different shapes, and/ormay be made of the same or different materials, amongst otherproperties. In some embodiments, less than all of the connectors 102have biasing portions 150. Connectors 102 without biasing portions 150may, for example, comprise one or more rigid connections between a rigidthird connector 108 and the attachment portion 140. In some embodiments,none of the connectors 102 of the appliance 100 have a biasing portion150.

According to some embodiments, for example as depicted schematically inFIG. 2A, the appliance 100 may include a single, continuous,substantially rigid third connector (referred to as “anchor 120”) and aplurality of flexible arms 130 extending away from the anchor 120. Whenthe appliance 100 is installed in the patient's mouth, each of the arms130 may connect to a different one of the teeth to be moved and exerts aspecific force on its respective tooth, thereby allowing an operator tomove each tooth independently. Such a configuration provides a notableimprovement over traditional braces in which all of the teeth areconnected by a single archwire, such that movement of one tooth cancause unintentional movement of one or more nearby teeth. Theindependent and customized tooth movement enabled by the appliances ofthe present technology allows the operator to move the teeth from anoriginal tooth arrangement (“OTA”) to a final tooth arrangement (“FTA”)more efficiently, thereby obviating periodic adjustments, reducing thenumber of office visits, and reducing or eliminating patient discomfort,and reducing the overall treatment time (i.e., the length of time theappliance is installed in the patient's mouth) by at least 50% relativeto the overall treatment time for traditional braces.

The anchor 120 may comprise any structure of any shape and sizeconfigured to comfortably fit within the patient's mouth and provide acommon support for one or more of the arms 130. In many embodiments, theanchor 120 is disposed proximate the patient's gingiva when theappliance 100 is installed within the patient's mouth, for example asshown in FIG. 2B. For instance, the appliance may be designed such that,when installed in the patient's mouth, all or a portion of the anchor120 is positioned below the patient's gum line and adjacent but spacedapart from the gingiva. In many cases it may be beneficial to provide asmall gap (e.g., 0.5 mm or less) between the anchor 120 (or any portionof the appliance 100) and the patient's gingiva as contact between theanchor 120 and the gingiva can cause irritation and patient discomfort.In some embodiments, all or a portion of the anchor 120 is configured tobe in contact with the gingiva when the appliance 100 is disposed in thepatient's mouth.

The anchor 120 may be significantly more rigid than the arms 130 suchthat the equal and opposite forces experienced by each of the arms 130when exerting a force on its respective tooth are countered by therigidity of the anchor 120 and the forces applied by the other arms 130,and do not meaningfully affect the forces on other teeth. As such, theanchor 120 effectively isolates the forces experienced by each arm 130from the rest of the arms 130, thereby enabling independent toothmovement.

According to some embodiments, for example as shown schematically inFIGS. 2A and 2B, the anchor 120 comprises an elongated member having alongitudinal axis L2 (see FIG. 2C) and forming an arched shapeconfigured to extend along a patient's jaw when the appliance 100 isinstalled. In these and other embodiments, the anchor 120 may be shapedand sized to span two or more of the patient's teeth when positioned inthe patient's mouth. In some examples, the anchor 120 includes a rigid,linear bar, or may comprise a structure having both linear and curvedsegments. In these and other embodiments, the anchor 120 may extendlaterally across all or a portion of the patient's mouth (e.g., acrossall or a portion of the palate, across all or a portion of the lowerjaw, etc.) and/or in a generally anterior-posterior direction. Moreover,the appliance 100 may comprise a single anchor or multiple anchors. Forexample, the appliance 100 may comprise multiple, discrete, spaced apartanchors, each having two or more arms 130 extending therefrom. In theseand other embodiments, the appliance 100 may include one or more otherconnectors extending between adjacent arms 130.

Any and all of the features discussed above with respect to anchor 120applies to any of the third connectors 108 disclosed herein.

As shown in FIG. 2B, each of the arms 130 may extend between a proximalor first end portion 130 a and a distal or second end portion 130 b, andmay have a longitudinal axis L extending between the first end portion130 a and the second end portion 130 b. The first end portion 130 a ofone, some, or all of the arms 130 may be disposed at the anchor 120. Insome embodiments, one, some, or all of the arms 130 are integral withthe anchor 120 such that the first end portion 130 a of such arms arecontinuous with the anchor 120. The arms 130 may extend from the anchor120 at spaced intervals along the longitudinal axis L2 of the, as shownin FIG. 2A. In some embodiments, the arms 130 may be spaced at evenintervals relative to each other, or at uneven intervals relative toeach other, along the longitudinal axis L2 of the anchor 120.

One, some, or all of the arms 130 may include an attachment portion 140at or near the second end portion 130 b. In some embodiments, forexample as shown in FIGS. 2A-2C, one or more of the arms 130 iscantilevered from the anchor 120 such that the second end portion 130 bof the cantilevered arm(s) 130 has a free distal end portion 130 b. Inthese and other embodiments, a distal terminus of the attachment portion140 may coincide with a distal terminus of the arm 130. The attachmentportion 140 may be configured to detachably couple the respective arm130 to a securing member (e.g., a bracket) that is bonded, adhered, orotherwise secured to a surface of one of the teeth to be moved. In someembodiments, the attachment portion 140 may be directly bonded, adhered,or otherwise secured to a corresponding tooth without a securing memberor other connection interface at the tooth.

Referring to still to FIGS. 2A and 2B, one, some, or all of the arms 130may include one or more resiliently flexible biasing portions 150, suchas springs, each configured to apply a customized force, torque orcombination of force and torque specific to the tooth to which it isattached. The biasing portion(s) 150 may extend along all or a portionof the longitudinal axis L1 of the respective arm 130 between the anchor120 and the attachment portion 140. The direction and magnitude of theforce and torque applied on a tooth by a biasing portion 150 depends, atleast in part, on the shape, width, thickness, length, material, shapeset conditions, and other parameters of the biasing portion 150. Assuch, one or more aspects of the arm 130 and/or biasing portion 150(including the aforementioned parameters) may be varied so that the arm130 and/or biasing portion 150 produce a desired tooth movement when theappliance 100 is installed in the patient's mouth. Each arm 130 and/orbiasing portion 150 may be designed to move one or more teeth in one,two, or all three translational directions (i.e., mesiodistal,buccolingual, and occlusogingival) and/or in one, two, or all threerotational directions (i.e., buccolingual root torque, mesiodistalangulation and mesial out-in rotation).

The biasing portions 150 of the present technology can have any length,width, shape, and/or size sufficient to move the respective toothtowards a desired FTA. In some embodiments, one, some, or all of thearms 130 may have one or more inflection points along a respectivebiasing portion 150. The arms 130 and/or biasing portions 150 may have aserpentine configuration such that the arm 130 and/or biasing portion150 doubles back on itself at least one or more times before extendingtowards the attachment portion 140. In FIG. 2B, the arm 130 doubles backon itself two times along the biasing portion 150, thereby forming firstand second concave regions facing in generally different directionsrelative to one another. The open loops or overlapping portions of thearm 130 corresponding to the biasing portion 150 may be disposed oneither side of a plane P bisecting an overall width W of the arm 130such that the extra length of the arm 130 is accommodated by the spacemedial and/or distal to the arm 130. This allows the arm 130 to have alonger length (as compared to a linear arm) to accommodate greater toothmovement, despite the limited space in the occlusal-gingival or verticaldimension between the anchor 120 and the location at which the arm 130attaches to the tooth.

It will be appreciated that the biasing portion 150 may have othershapes or configurations. For example, in some embodiments the arm 130and/or biasing portion 150 may include one or more linear regions thatzig-zag towards the attachment portion 140. One, some, or all of thearms 130 and/or biasing portions 150 may have only linear segments orregions, or may have a combination of curved and linear regions. In someembodiments, one, some, or all of the arms 130 and/or biasing portions150 do not include any curved portions.

According to some examples, a single arm 130 may have multiple biasingportions 150. The multiple biasing portions 150 may be in series alongthe longitudinal axis L1 of the respective arm 120. In some embodiments,multiple arms 130 may extend in parallel between two points along thesame path or along different paths. In such embodiments, the differentarms 130 may have the same stiffness or different stiffnesses.

In those embodiments where the appliance 100 has two or more arms 130with biasing portions 150, some, none, or all of the arms 130 may havethe same or different lengths, the same or different widths, the same ordifferent thicknesses, the same or different shapes, and/or may be madeof the same or different materials, amongst other properties. In someembodiments, less than all of the arms 130 have biasing portions 150.Arms 130 without biasing portions 150 may, for example, comprise one ormore rigid connections between the anchor 120 and the attachment portion140. In some embodiments, none of the arms 130 of the appliance 100 havea biasing portion 150.

The appliances of the present technology may include any number of arms130 suitable for repositioning the patient's teeth while taking intoaccount the patient's comfort. Unless explicitly limited to a certainnumber of arms in the specification, the appliances of the presenttechnology may comprise a single arm, two arms, three arms, five arms,ten arms, sixteen arms, etc. In some examples, one, some, or all of thearms 130 of the appliance may be configured to individually connect tomore than one tooth (i.e., a single arm 130 may be configured to coupleto two teeth at the same time). In these and other embodiments, theappliance 100 may include two or more arms 130 configured to connect tothe same tooth at the same time.

Any portion of the appliances of the present technology may include abiasing portion 150. For example, in some embodiments, portions thereof(e.g., the anchor(s), the arm(s), the biasing portion(s), the attachmentportion(s), the link(s), etc.) may comprise one or more superelasticmaterials.

Additional details related to the individual directional force(s)applied via the biasing portion 150 or, more generally the arm 130, aredescribed in U.S. application Ser. No. 15/370,704, now U.S. Pat. No.10,383,707, issued Aug. 20, 2019, the disclosure of which isincorporated by reference herein in its entirety.

The appliances disclosed herein and/or any portion thereof (e.g., theanchor(s), the arm(s), the biasing portion(s), the attachmentportion(s), the link(s), etc.) may comprise one or more superelasticmaterials. The appliances disclosed herein and/or any portion thereof(e.g., the anchor(s), the arm(s), the biasing portion(s), the attachmentportion(s), the link(s), etc.) may comprise Nitinol, stainless steel,beta-titanium, cobalt chrome, MP35N, 35N LT, one or more metal alloys,one or more polymers, one or more ceramics, and/or combinations thereof.

FIGS. 3A and 3B are elevation views of the appliance 100 installed onboth the upper and lower arches of a patient's mouth with the arms 130coupled to securing members 160 attached to the lingual surfaces of theteeth. It will be appreciated that the appliance 100 of one or both ofthe upper and lower arches may be positioned proximate a buccal side ofa patient's teeth, and that the securing members 160 and/or arms 130 mayalternatively be coupled to the buccal surface of the teeth.

FIG. 3A shows the teeth in an OTA with the arms 130 in a deformed orloaded state, and FIG. 3B shows the teeth in the FTA with the arms 130in a substantially unloaded state. When the arms 130 are initiallysecured to the securing members 160 when the teeth are in the OTA, thearms 130 are forced to take a shape or path different than their “asdesigned” configurations. Because of the inherent memory of theresilient biasing portions 150, the arms 130 impart a continuous,corrective force on the teeth to move the teeth towards the FTA, whichis where the biasing portions 150 are in their as-designed or unloadedconfigurations. As such, tooth repositioning using the appliances of thepresent technology can be accomplished in a single step, using a singleappliance. In addition to enabling fewer office visits and a shortertreatment time, the appliances of the present technology greatly reduceor eliminate the pain experienced by the patient as the result of theteeth moving as compared to braces. With traditional braces, every timethe orthodontist makes an adjustment (such as installing a new archwire,bending the existing archwire, repositioning a bracket, etc.), theaffected teeth experience a high force which is very painful for thepatient. Over time, the applied force weakens until eventually a newwire is required. The appliances of the present technology, however,apply a movement-generating force on the teeth continuously while theappliance is installed, which allows the teeth to move at a slower ratethat is much less painful (if painful at all) for the patient. Eventhough the appliances disclosed herein apply a lower and less painfulforce to the teeth, because the forces being applied are continuous andthe teeth can move independently (and thus more efficiently), theappliances of the present technology arrive at the FTA faster thantraditional braces or aligners, as both alternatives requireintermediate adjustments.

In many embodiments, the movement-generating force is lower than thatapplied by traditional braces. In those embodiments in which theappliance comprises a superelastic material (such as nitinol), thesuperelastic material behaves like a constant force spring for certainranges of strain, and thus the force applied does not drop appreciablyas the tooth moves. For example, as shown in the stress-strain curves ofnitinol and steel in FIG. 3C, the curve for nitinol is relatively flatcompared to that of steel. Thus, the superelastic connectors, biasingportions, and/or arms of the present technology apply essentially thesame stress for many different levels of strain (e.g., deflection). As aresult, the force applied to a given tooth stays constant as the teethmove during treatment, at least up until the teeth are very close or inthe final arrangement. The appliances of the present technology areconfigured to apply a force just below the pain threshold, such that theappliance applies the maximum non-painful force to the tooth (or teeth)at all times during tooth movement. This results in the most efficient(i.e., fastest) tooth movement without pain.

Embodiments involving multiple steps (or multiple appliances, or both)may include one or more intermediate tooth arrangements (ITAs) betweenan original tooth arrangement (OTA) and a desired final tootharrangement (FTA). Likewise, the appliances disclosed herein may bedesigned to be installed after a first or subsequently used appliancehad moved the teeth from an OTA to an ITA (or from one ITA to anotherITA) and was subsequently removed. Thus, the appliances of the presenttechnology may be designed to move the teeth from an ITA to an FTA (orto another ITA). Additionally or alternatively, the appliances may bedesigned to move the teeth from an OTA to an ITA, or from an OTA to anFTA without changing appliances at an ITA.

In some embodiments, the appliances disclosed herein may be configuredsuch that, once installed on the patient's teeth, the appliance cannotbe removed by the patient. In some embodiments, the appliance may beremovable by the patient.

Any of the example appliances or appliance portions described herein maybe made of any suitable material or materials, such as, but not limitedto Nitinol (NiTi), stainless steel, beta-titanium, cobalt chrome orother metal alloy, polymers, or ceramics, and may be made as a single,unitarily-formed structure or, alternatively, in multipleseparately-formed components connected together in single structure.However, in particular examples, the rigid bars, bracket connectors andloop or curved features of an appliance (or portion of an appliance)described in those examples are made by cutting a two dimensional (2D)form of the appliance from a 2D sheet of material and bending the 2Dform into a desired 3D shape of the appliance, according to processes asdescribed in U.S. Pat. No. 10,383,707, U.S. patent application Ser. No.15/929,442 (Publ. No. 2020/0345455), filed May 2, 2020, or othersuitable processes.

III. Selected Methods for Manufacturing Orthodontic Appliances andFixtures

Several of the methods disclosed herein can be performed using one ormore aspects of a manufacturing system. The system can include animaging device configured to be communicatively coupled to a computingdevice. The imaging device can include any suitable device or collectionof devices configured to obtain image data or other digitalrepresentation of a patient's teeth, gingiva, and other dental anatomy.For example, the imaging device can include an optical scanning device(e.g., as commercially sold by ITERO, 3 SHAPE, and others), a cone-beamcomputed tomography scanner, or any other suitable imaging device.

The computing device can be any suitable combination of software andhardware. For example, the computing device can include a specialpurpose computer or data processor that is specifically programmed,configured, or constructed to perform one or more of thecomputer-executable instructions explained in detail herein.Additionally or alternatively, the computing device can include adistributed computing environment in which tasks or modules areperformed by remote processing devices, which are linked through acommunication network (e.g., a wireless communication network, a wiredcommunication network, a cellular communication network, the Internet, ashort-range radio network (e.g., via Bluetooth)). In a distributedcomputing environment, program modules may be located in both local andremote memory storage devices.

Computer-implemented instructions, data structures, and other data underaspects of the technology may be stored or distributed oncomputer-readable storage media, including magnetically or opticallyreadable computer disks, as microcode on semiconductor memory,nanotechnology memory, organic or optical memory, or other portableand/or non-transitory data storage media. In some embodiments, aspectsof the technology may be distributed over the Internet or over othernetworks (e.g. a Bluetooth network) on a propagated signal on apropagation medium (e.g., an electromagnetic wave(s), a sound wave) overa period of time, or may be provided on any analog or digital network(packet switched, circuit switched, or other scheme).

The system can also include one or more input devices (e.g., touchscreen, keyboard, mouse, microphone, camera, etc.) and one or moreoutput devices (e.g., display, speaker, etc.) configured to becommunicatively coupled to the computing device. In operation, a usercan provide instructions to the computing device and receive output fromthe computing device via the input and output devices.

The computing device may be configured to be communicatively connectedto one or more fabricating systems (including fabricating machines) forfabricating appliances, shape setting fixtures, and any other componentsthereof and associated tools, as described herein. The computing devicecan be connected to the fabricating system(s) by any suitablecommunication connection including, but not limited to a directelectronic connection, network connection, or the like. Alternatively,or in addition, the connection may be provided by delivery to thefabricating system of a physical, non-transient storage medium on whichdata from the computing device has been stored.

Methods of Designing Orthodontic Appliances and Fixtures

FIG. 4 is a flow diagram of a process 400 for making an orthodonticappliance. The process 400 begins at block 402 with obtaining a digitalmodel of the patient's teeth and/or surrounding anatomy (such as thegingiva) in the OTA. The process 400 continues at block 404 withobtaining a digital model of the patient's teeth and/or surroundinganatomy in the FTA. Next the process 400 comprises obtaining a digitalmodel (block 406) of a fixture for shape setting the appliance. Theprocess 400 further includes obtaining an appliance digital model (block408). As shown at blocks 410 and 412, the process 400 continues withfabricating the fixture and fabricating the appliance. Finally, theprocess 400 includes shape setting the appliance using the fixture(block 414). While the foregoing steps are presented in a particularorder, it will be appreciated they need not be executed in the presentedorder. For example, in some embodiments obtaining the appliance digitalmodel occurs prior to and/or at the same time as obtaining the fixturedigital model. In other embodiments, obtaining the appliance digitalmodel occurs after and/or at the same time as obtaining the fixturedigital model.

FIG. 5 is a flow diagram of an example process 500 for making anorthodontic appliance of the present technology. The process 500 beginsat block 502 with obtaining data characterizing an OTA. For example, asshown in FIG. 6, the OTA data can be obtained by scanning the patient'steeth using an intraoral optical scanner 600. Such a scanner 600 can beused to scan the patient's oral anatomy to obtain data characterizing aproperty (e.g., a shape, a color, a material property, etc.) of theanatomy. For example, the scanner 600 can be used to scan the patient'supper dental arch, the patient's lower dental arch, one or more of thepatient's teeth, the patient's oral tissues (such as gingival tissue),and/or the patient's oral or facial bones. The scanning can be performedusing any suitable technique, for example using a dental cone beam CTscanner, a magnetic resonance imaging (MRI) device, or a similar deviceor technique. In some examples, the OTA data can be obtained using animpression made of the patient's upper and lower jaws (e.g., usingpolyvinyl siloxane or any other suitable impression material). Theimpression can then be scanned to create 3D data, which can include therelationship between the upper and lower jaw (e.g., to record thepatient's bite). In examples in which impressions are used, therelationship between the teeth in the upper and lower arches (inter-archrelationship) can be obtained by taking a wax bite of the patient in thecentric position. In various embodiments, the OTA data can be obtaineddirectly (e.g., by imaging the patient's mouth using an appropriateimaging device) or indirectly (e.g., by receiving pre-existing OTA datafrom an operator or another source).

The OTA data can include data characterizing the roots of the teeth aswell as the exposed portions (e.g., the crowns), which may beadvantageous in designing an appropriate orthodontic appliance.Additionally or alternatively, the OTA data can include datacharacterizing the patient's oral tissues such as the gingiva, palate,tongue, etc.

In some embodiments, the OTA data comprises a point cloud including aplurality of points and coordinates associated with each point.According to various embodiments, the OTA data can comprise image data.For example, the OTA data can comprise one or more 2D images obtained,for example, via mobile phone imaging, CT scanning, MRI, etc.

Returning to FIG. 5, the process 500 continues with obtaining an OTAdigital model at block 504. FIG. 7 is a graphical representation of anexample of an OTA digital model 700. The digital model 700 can virtuallyrepresent or characterize the arrangement of the patient's teeth andgingiva in the original tooth arrangement. As seen in FIG. 7, the teethin the OTA may be maloccluded, mis-aligned, crowded, or otherwise inneed of orthodontic correction. In some embodiments, one or more teethpresent in the OTA may be designated for extraction prior to use of theorthodontic appliance. The OTA digital model 700 can include a teethportion 702 comprising one, some, or all of the patient's teeth and agingiva portion 704.

In some embodiments, the OTA digital model comprises a mesh model (e.g.,a triangle mesh model, a polygon mesh model, a volumetric mesh model,etc.), a surface model (e.g., a non-uniform rational basis spline(NURBS) surface model, a T-Spline surface model, etc.), a parametric CADmodel, or another suitable type of model. The OTA digital model can bebased, at least in part, on the OTA data. For example, if the OTA datacomprises a point cloud, obtaining the OTA digital model can compriseconverting the point cloud to a 3D surface model via surfacereconstruction methods. Such surface reconstruction methods can include,for example, Delaunay triangulation, alpha shapes, ball pivoting, orother suitable methods. In some embodiments, a 3D OTA digital model canbe obtained from two or more 2D images. For example, OTA data comprisinga plurality of 2D images obtained via CT scanning can be segmented toidentify portions of the images that correspond to one or more specificanatomical feature (e.g., bone, soft tissue, a specific tooth or teeth,the mandible, the maxilla, the skull, etc.) and a 3D model can begenerated from the segmented image data.

In some embodiments, obtaining the OTA digital model corresponding tothe OTA data can include first obtaining a single complex 3D database ofthe patient's jaw, which is then segmented to separate the patient'steeth into separate 3D bodies (e.g., individual teeth or blocks ofmultiple teeth) that can then be manipulated virtually by an operator.In embodiments in which the OTA digital model comprises a mesh model, asingle, continuous mesh model of the patient's jaw can be segmented toobtain two or more mesh models each characterizing one of the patient'steeth or gingiva. For example, one digital model in an STL file formatcan be segmented into two or more individual STL files. Suchsegmentation can be performed using any suitable techniques or software.Following segmentation, the resulting 3D databases of upper and lowerteeth can include a model of the gingiva and an independent model ofeach tooth. As a result, the OTA data can be manipulated by an operatorto virtually move teeth relative to the gingiva. For example, at processportion 506, the teeth can be manipulated from the OTA towards a finaltooth arrangement (FTA) to obtain FTA data. FIG. 8 illustrates anexample digital model 800 of an FTA. Similar to the OTA digital model700, the FTA digital model 800 includes a teeth portion 802 and agingiva portion 804. The FTA digital model 800 can be based at least inpart on data characterizing the teeth in the FTA. Such FTA data caninclude a digital representation of the desired final positions andorientations of the patient's teeth relative to one another and to thegingiva. The FTA data can be obtained directly (e.g., generated by theoperator) or may be received from an external source (e.g., the FTA datamay be generated by a third party and provided to an operator for designof an appropriate orthodontic appliance). In some cases, virtualmovement of the teeth relative to the OTA also results in movement ofthe virtual gingiva (relative to the virtual gingiva in the OTA) inorder to maintain the natural look of the gingiva and more accuratelyreflect the orientation and position of the gingiva when the teeth areat the FTA. This movement of the gingiva can be achieved using gingivamorphing or other suitable techniques. Accordingly, in some embodiments,the gingiva portion 804 in the FTA digital model 800 is different thanthe gingiva portion 704 in the OTA digital model 700. In someembodiments the gingival surface is not affected by the movement of theteeth and the gingiva portions 804, 704 of the FTA and OTA digitalmodels 800, 700 are substantially the same.

As seen in FIG. 8, the teeth in the FTA digital model may be morealigned, less mal-occluded, and otherwise aesthetically and functionallyimproved relative to the OTA digital model 700. In some embodiments, theFTA can have desired or favorable inter-arch and intra-archarrangements, for example, based on an operator's prescription. Forexample, one or more (or all) teeth from the upper or lower jaws (orboth) are moved until their cusps have a good interdigitation and fit.

According to various embodiments, obtaining the OTA digital model and/orobtaining the FTA digital model can comprise obtaining a localcoordinate system for one or more portions of the model. For example, inembodiments in which the OTA digital model comprises a plurality ofindividual models representing individual teeth of a patient, a localcoordinate system can be obtained for one or more of the teeth. In someembodiments, the local coordinate system comprises three orthogonalaxes. One or more of the three axes can substantially correspond to anocclusogingival dimension of the tooth, a buccolingual dimension of thetooth, and/or a mesiodistal dimension of the tooth. Additionally oralternatively, the axes can comprise other standard anatomical axes(e.g., anteroposterior, mediolateral, longitudinal, etc.) or othersuitable axes. An origin of a local coordinate system of a tooth can belocated at a center of mass of the tooth, a center of mass of the crownof the tooth, a surface of the tooth, or another suitable location. Thelocation of the origin of the local coordinate system can be selected tofacilitate moving and/or aligning the individual tooth models in adigital environment. The local coordinate system for each individualtooth model in the OTA or FTA digital model can be unique to thespecific tooth. In some embodiments, the local coordinate systems fortwo or more individual tooth models can be the same. According tovarious embodiments, a local coordinate system can be defined for anynumber or combination of portions of a digital model of the presenttechnology (e.g., an OTA digital model, an FTA digital model, etc.). Forexample, a local coordinate system can be defined for each of the teethin one of the patient's dental arches, each of the teeth in one of thepatient's dental arches and the surrounding bone of the correspondingjaw (e.g., the mandible or the maxilla), each of the teeth in both ofthe patient's dental arches, combinations thereof, and/or others.

In some embodiments, individual models of a patient's teeth in an OTAdigital model can be virtually moved with reference to the localcoordinate system of the tooth to generate an FTA digital model. Invarious embodiments, a human operator can view and/or interact with thedigital models disclosed herein in a digital environment, e.g., via auser interface. The operator can specify a desired movement of one ormore of the individual tooth models along and/or about the axes of thelocal coordinate system of the tooth model. For example, the operatorcan select (e.g., via an input device such as a mouse) a graphicalrepresentation of an axis of a local coordinate system (or a portionthereof) of a tooth model to move the tooth. In some embodiments,selecting the graphical representation of the axis changes the positionof the tooth model in the digital environment by a predeterminedtranslation along the axis and/or rotation about the axis. In someembodiments, the operator can select a graphical representation of anallowable movement of an individual tooth model (e.g., a rotation aboutan axis of a local coordinate system, a translation along an axis of alocal coordinate system, etc.) to move the tooth model in the directionof the allowable movement. In some embodiments, selection of thegraphical representation of the allowable movement moves the tooth modelby a predetermined distance. Additionally or alternatively, an operatorcan select and drag the graphical representation of the local coordinatesystem (or a portion thereof) and/or the graphical representation of oneor more allowable movements to move the tooth model. A magnitude of thevirtual movement of the tooth model can be based, at least in part, onthe duration and/or distance of the drag. In some examples, the operatorcan select the tooth model directly to move the tooth model by apredetermined amount and/or the operator can select and drag the toothmodel directly to move the tooth model by an amount is based on the dragduration and/or distance. In various embodiments, the digitalenvironment can include an input field into which an operator can entera numerical value for a desired movement of the tooth. For example, thedigital environment can comprise input fields for translations along theaxes of the tooth local coordinate system and/or rotations about theaxes of the tooth local coordinate system. According to variousembodiments, movement of the teeth in the digital environment can beperformed automatically. For example, processors of a computing devicecan be configured to move the teeth to accomplish an objective such asreducing a contact between adjacent teeth, reducing excessive spacingbetween the teeth, etc.

Referring back to FIG. 5, the process 500 continues in block 508 withobtaining securing member digital model(s). As discussed previously,securing members (e.g., securing members 160, brackets, etc.) can becoupled to the patient's teeth to allow for an orthodontic appliance(e.g., appliance 100) to be mated thereto. The securing member digitalmodels can include a virtual representation of the geometry and/or otherstructural characteristics of the securing member(s). The securingmember digital model(s) can comprise a mesh model, a parametric CADmodel, or any other suitable type of digital model. In variousembodiments, the securing member digital models can be identical foreach securing member, or may vary among the securing members. Forexample, different securing members may be used for molars than forincisors. FIG. 9 illustrates an example securing member digital model900.

With continued reference to FIG. 5, the process 500 continues in block510 with obtaining an OTA digital model with securing members positionedon the teeth. For example, a securing member digital model 900 (FIG. 9)can be applied to appropriate locations on the patient's teeth withinthe OTA digital model 700 (FIG. 7). The resulting digital model 1000 isshown in FIG. 10, in which a plurality of digital models of securingmembers 900 are disposed at the lingual surfaces of the patient's teeth.In some embodiments, the securing members 900 are disposed at the buccalsurfaces of the patient's teeth. The securing member can be positionedon one, some, or all of the teeth of the OTA digital model 700. In someembodiments the process 500 does not include obtaining an OTA digitalmodel with securing members.

In some examples, the digital models 900 of the securing members can bevirtually positioned on the teeth in the OTA using appropriate software.In some embodiments, virtually positioning the securing members caninclude selecting virtual models of particular securing members from alibrary of available securing members, and then virtually positioningthe selected securing members on one or more teeth. In some embodiments,the bracket positioning can be assigned automatically (e.g., byautomatically positioning the bracket in a central or the pre-definedportion of the tooth) or manually (e.g., by an operator selecting and/ormanipulating the attachment location for each securing member). In someembodiments, the position of each securing member can be refined by theoperator as desired. For example, it may be desirable to position thesecuring members as close to the gingiva as possible so as to avoidinterference with securing members on the other jaw or interference withthe teeth from the other jaw when the mouth is closed. In variousembodiments, the desired position of a securing member on one tooth maybe different than the desired position of a securing member on anothertooth. For example, it may be advantageous to position securing memberson the anterior teeth gingivally to prevent or limit collision ofsecuring members on the upper and lower jaws during chewing, while itmay be advantageous to position securing members on the posterior teethat mesial portions and/or distal portions of the posterior teeth toprevent or limit undesired rotation of the posterior teeth duringclosing of a space resulting from extraction of one or more of thepatient's teeth.

In some embodiments, the OTA digital model with securing members 1000can be used to determine a configuration of a bonding tray, which maythen be used to physically attach securing members to the patient'steeth by an operator. For example, the bonding tray can be configured tofit over the patient's teeth similar to an aligner, and can includerecesses on a side of each tooth that are sized and configured toreceive an appropriate securing member (e.g., bracket) therein. Invarious embodiments, such recesses can be positioned on the lingual,buccal, mesial/distal, occlusal, root, or any suitable surface of atooth to which a corresponding bracket is intended to be bonded. Inoperation, an appropriate securing member can be placed in each recessof the bonding tray and then an adhesive (e.g., an adhesive that cureswhen illuminated by ultraviolet light) can be applied to the bondingsurface of each securing member. The tray can then be placed over thepatient's teeth and the adhesive cured to bond all the securing membersto the appropriate location on each tooth.

To generate such a bonding tray, the OTA digital model with securingmembers 1000 can be manipulated, for example, to remove excess virtualgingiva to limit the size of the tray to only what is necessary to holdthe securing members in position against the patient's teeth.

The trimmed digital model can then be used to generate a physical 3Dmodel of the patient's teeth with the securing members disposed thereon,for example using 3D printing in a polymer resin or other suitabletechnique. In some embodiments, a suitable material (e.g., a clearpolymer resin) can then be formed over (e.g., thermoformed over) thephysical model of the patient's teeth with securing members in the OTA.This can create the aligner-like tray with recesses shaped andconfigured to receive securing members therein. The securing members canthen be placed into corresponding recesses of the tray, and the tray canbe applied to the patient's teeth with a curable adhesive to attach thesecuring members to the patient's teeth in the OTA. The tray may then beremoved, leaving the securing members in place.

In some embodiments, the bonding tray can be 3D printed directly,without the need for a physical model of the patient's teeth and withoutthe use of thermoforming. For example, a digital model of a bonding traycan be derived from the digital model 1000 characterizing the teeth inthe OTA with securing members attached. In some embodiments, a negativeof the digital model 1000 can be generated then trimmed to provide ageneral tray-like structure with a surface corresponding to the teethand securing members in the digital model 1000. This resulting model canbe manipulated to provide features for retaining brackets in thecorresponding recesses. Finally, the bonding tray can be 3D printedbased on this digital model, for example using 3D printable polymerresins or other suitable materials or deposition techniques.

Alternatively, the operator may attach securing members to the patient'steeth directly, without the assistance of a tray.

Referring back to FIG. 5, the process 500 continues at block 512 withobtaining an FTA digital model. In some embodiments, the FTA digitalmodel is generated using the OTA digital model without the securingmembers (as shown in FIGS. 7 and 8) and the securing members can laterbe added to the FTA digital model. In some embodiments, the FTA digitalmodel is generated using the OTA digital model with the securingmembers. In either case, the process 500 includes obtaining an FTAdigital model with securing members, an example of which is shown inFIG. 11. As depicted, the FTA digital model 1100 with securing members900 comprises a teeth portion 1102 and a gingiva portion 1104. The FTAdigital model with securing members 1100 can be based at least in parton data characterizing the teeth in the FTA. Such FTA data can include adigital representation of the desired final positions and orientationsof the patient's teeth relative to one another and to the gingiva. TheFTA data can be obtained directly (e.g., generated by the operator) ormay be received from an external source (e.g., the FTA data may begenerated by a third party and provided to an operator for design of anappropriate orthodontic appliance).

As previously mentioned, in some embodiments the FTA data can beobtained by manipulating the OTA data to virtually move the patient'steeth. Suitable software can be used by an operator to move the teeth toa desired FTA. For example, a tooth of the OTA digital model can bemoved based on translations and/or rotations of the tooth relative to alocal coordinate system. In some cases, virtual movement of the teethrelative to the OTA also results in movement of the virtual gingiva(relative to the virtual gingiva in the OTA) in order to maintain thenatural look of the gingiva and more accurately reflect the orientationand position of the gingiva when the teeth are at the FTA. This movementof the gingiva can be achieved using gingiva morphing or other suitabletechniques. The gingiva portion 1104 of the FTA digital model withsecuring members may be the same as or different than the gingivaportion 704 of the OTA digital model.

In some embodiments, the FTA can reflect changes to the patient's teeththat may occur as part of the treatment process. For example, anoperator may extract one or more teeth of the patient as part of thetreatment (for example because of lack of space for all of the teeth tofit in the arch or other reasons). In that event, the extracted teethcan be excluded from the FTA data. If the operator decides that theteeth need to become smaller due to a lack of space, then interproximalreduction (IPR) may be performed on the patient. In this case, strippingand reducing the size of the teeth in the FTA can be performed so as tomatch the IPR done by the operator.

In some embodiments, a proposed FTA can be developed by an operator(e.g., independently or based in whole or in part on input from atreating orthodontist) and then sent to a treating orthodontist forreview and comment. If the treating orthodontist has comments, she canprovide input to the operator (e.g., written notes, proposedmanipulation of one or more teeth or securing members, etc.) that can betransmitted electronically or otherwise. The operator may then revisethe FTA and send a revised proposed FTA back to the treatingorthodontist for further review and comment. This iterative process mayrepeat until the treating orthodontist approves the proposed FTA, andthe resulting digital model 1100.

Referring still to FIG. 5, the process 500 continues at block 514 withdetermining the displacements of individual teeth or groups or teethbetween the OTA and the FTA. For example, the displacement of each toothbetween the OTA and FTA can be described using six degrees of freedom(e.g., translation along X, Y, and Z axes, and rotation around the samethree axes; or alternatively translation along mesiodistal,buccolingual, and/or occlusogingival directions, and rotation in theform of buccolingual root torque, mesiodistal angulation, and/or mesialout-in rotation). In some embodiments, these values can be determined bycalculating the difference between the location of each tooth in the FTAdata and the OTA data. This can be performed for each tooth in each jawto generate a dataset that includes the required displacement along sixdegrees of freedom for each tooth.

In some embodiments, the process 500 can include evaluating proposeddisplacements of the patient's teeth and, based on the evaluation,modifying the proposed displacements and/or final positions of thepatient's teeth. For example, the process 500 can include decomposing anoverall displacement of one or more of the patient's teeth intocomponent displacements. A component displacement can comprise a commondisplacement of all of the patient's teeth, a common displacement of allof the teeth in one of the patient's dental arches, a displacement thatis unique to an individual tooth, or another displacement of one or moreteeth. Additional details relating to evaluating and modifying proposedfinal positions and/or planned displacements are described with respectto FIGS. 19-32E.

The process 500 continues at block 516 with obtaining a digital model ofa fixture that, in its physical form, is used to shape set theappliance. FIG. 12 illustrates an example fixture digital model 1200,which can be generated by manipulating the digital model of the OTA, thedigital model of the FTA, the digital model of the OTA with securingmembers attached, and/or the digital model of the FTA with securingmembers attached. The digital model(s) 700, 800, 1000, 1100 can bemanipulated in a number of ways to generate suitable fixture data.

As shown in FIG. 12, the fixture digital model 1200 can comprise one ormore securing portions 1202 and a gingiva portion 1210. In theirphysical form, the securing portions 1202 can be configured toreleasably retain one or more portions of an appliance at a specificlocation relative to other portions of the appliance. For example, thesecuring portions 1202 can be configured to retain attachment portions(e.g., attachment portions 140, etc.) of an appliance during a shapesetting procedure in positions corresponding to intended positions ofcorresponding securing members when the appliance is later installed inthe patient's mouth and the securing members are secured to thepatient's teeth (for example, when the teeth, and thus securing members,are in an OTA or FTA). In some embodiments, the securing portions 1202are positioned relative to one another and to the gingiva portion 1210to reflect the positions of the teeth in the FTA. In other embodiments,the securing portions 1202 are positioned to reflect the teeth in theOTA or an ITA.

The fixture model can be generated based on one, some, or all of the OTAand FTA digital models (with and/or without the securing members). Insome embodiments, the fixture digital model 1200 can be generated byusing one of the FTA digital models to position the securing portions1202 of the fixture digital model 1200 at desired locations and mergingthe digital model of the securing portions 1202 with a digital model ofthe patient's gingiva obtained from one of the OTA digital models. Forexample, generating the fixture digital model 1200 can include obtainingthe “FTA with securing members” digital model and one-by-one replacingindividual securing members with individual securing portions such thatthe securing portions are located at positions corresponding topositions of the securing members in the “FTA with securing members”digital model. In some embodiments, positioning a digital model of asecuring portion (e.g., securing portion 1202, etc.) at a positioncorresponding to a position of a securing member in the “FTA withsecuring members” digital model comprises aligning a local coordinatesystem of the securing portion digital model with a local coordinatesystem of the securing member digital model, which can comprisepositioning an origin of the local coordinate system of the securingportion digital model at a position of an origin of the local coordinatesystem of the securing member digital model. In some cases, axes of thelocal coordinate system of the securing portion digital model can bealigned with axes of the local coordinate system of the securing memberdigital model. Additionally or alternatively, the securing portiondigital model can be transformed to align the axes of the localcoordinate systems.

Once the securing portions 1202 are positioned at their intendedlocations, the portions of the FTA with securing members digital modelcorresponding to the securing members, the teeth, and/or the gingiva canbe deleted. Additionally or alternatively, the securing members can bereplaced with the securing portions in a single step. The resultingdigital model can be saved as the fixture digital model 1200 or acomponent digital model thereof. In some embodiments, obtaining thefixture digital model 1200 comprises merging two or more digital models.For example, obtaining the fixture digital model 1200 can comprisemerging the individual digital models of the securing portions 1202 attheir intended positions with an individual digital model of the gingivaportion 1210 of the fixture. According to various embodiments, suchindividual digital model of the gingiva portion 1210 can be obtainedfrom one of the OTA digital models.

In some embodiments, merging the individual models of the securingportions 1202 at their intended positions with an individual digitalmodel of the gingiva portion 1210 can comprise extruding a surface ofone or more of the models of the securing portions 1202 to meet themodel of the gingiva portion 1210, or vice versa. Such extrusion may beuseful or necessary because a securing member, and therefore acorresponding securing portion, will often be positioned occlusally ofthe patient's gingiva. In such examples, it can be advantageous toextend the securing portion and/or the gingiva to meet one another suchthat the securing portions and gingiva comprise a single, continuousstructure. Extruding a surface of a securing portion to meet the gingivacan comprise obtaining one or more references (e.g., points, lines,surfaces, and/or other features) of the digital model of the securingportion 1202, obtaining one or more corresponding references (e.g.,points, lines, surfaces, and/or other features) of the digital model ofthe gingiva portion 1210, and/or obtaining an extrusion path based onthe references of the securing portion and/or the gingiva portion. Asbut one example, a unique identifier can be assigned to certaindistinctive reference points on the securing portion digital model. Suchidentifiers can comprise a label or a property (e.g., a color, anopacity, etc.). Additionally or alternatively, such reference points cancomprise vertices defining a boundary of a surface of the securingportion digital model. An operator or a processor can identify thereference points and/or distinguish the reference points from the restof the digital model based on the unique identifiers of the referencepoints. In some embodiments, identifying the reference points comprisesidentifying 3D coordinates of the reference points. In theseembodiments, and in others, obtaining corresponding references of thegingiva portion digital model can comprise identifying points, lines,features, etc. of the gingiva portion digital model that are the closestand/or most similar to the references of the securing portion digitalmodel.

In some embodiments, to obtain the fixture digital model 1200, thedigital model(s) 700, 800 without securing members and/or the digitalmodel(s) 1000, 1100 with securing members can be manipulated to removethe teeth or other structural elements not needed for shape setting theappliance, and/or to add structural features to reinforce the fixturefor sufficient rigidity during the heat treatment process. For example,as shown in FIG. 12, the fixture model 1200 does not include any teeth,but retains at least a portion of the gingiva portion 1210.Additionally, the fixture model 1200 includes a stabilizing crossbar1212 that can enhance the rigidity of the resulting fixture. Variousother modifications to the digital model(s) 700, 800, 1000, 1100 can bemade to achieve the desired fixture model 1200.

The securing portions 1202 can have a geometry configured to facilitatepositioning and/or retaining corresponding attachment portions at theintended positions. For example, as shown in FIG. 12, the securingportions 1202 can define first channels 1204 and second channels 1206angled with respect to the first channels 1204. The first and secondchannels 1204, 1206 are configured to receive attachment portions of anappliance at least partially therein to locate the attachment portionsat their intended positions. The securing portions 1202 can compriseprotrusions (e.g., protrusions 1208) extending away from thecorresponding securing portion 1202 and defining channels. In someembodiments, the protrusions 1208 define the first and second channels1204, 1206 and/or the protrusions 1208 can define third channelsconfigured to receive a fastener at least partially therein. Forexample, an elongate member such as a ligature wire can be wound aboutone of the securing portions 1202 and an attachment portion of anappliance such that the ligature wire is positioned within channelsdefined by the protrusions 1208 and secures the attachment portion tothe securing portion 1202. The securing portions 1202 can be configuredto receive and/or coupled with other fasteners, such as ties, sutures,bands, clasps, and others. In various embodiments, the securing portions1202 can define one or more through-channels, apertures, or otheropenings to facilitate securing of an attachment portion to the securingportion 1202 via a fastener. For example, such openings can allow apushing tool to be inserted from the back of the securing portion 1202(e.g., through the buccal surface of the fixture model 1200) to push anattachment portion 140 away from the securing portion 1202 after theheat treatment has been completed and the ligature wire or otherfastener has been removed.

The gingiva portion 1210 of the fixture model 1200 can be a virtualrepresentation of gingival tissue and, in its physical form, provides asurface on which a portion of the appliance is conformed during a shapesetting procedure. The gingiva portion 1210 may be substantiallyidentical to the gingiva portion from any of the OTA or FTA digitalmodels (e.g., 700, 800, 1000, 1100). For example, it can be desirable touse the gingiva portion 704 from the OTA digital model 700 for thegingiva portion 1210 of the fixture model 1200 to prevent or limitimpingement of the patient's gingiva by an appliance having a shapebased on the fixture model 1200 when the appliance is installed. In somecases, the securing portions 1202 can be positioned to reflect the teethin the FTA while the gingiva portion 1210 reflects the gingiva in theOTA.

In some embodiments, the gingiva portion 1210 of the fixture model 1200is a modified version of the gingiva portions from any of the OTA or FTAdigital models (e.g., 700, 800, 1000, 1100). When an appliance isinstalled, a patient may experience considerable discomfort if anyportion of the appliance impinges on the gingiva. On the other hand, itis desirable to have the appliance as close to the gingiva as possibleto reduce irritation of the tongue (if a lingual device) or lips (if abuccal device). Accordingly, it can be desirable to design the applianceand/or fixture so that the appliance rests as close to the patient'sgingiva as possible without impinging. To achieve this balance, in someembodiments the fixture model has a gingiva portion 1210 with a modifiedshape and/or size relative to the shape and/or size of the gingiva ofthe OTA digital model, the FTA digital model, the OTA digital model withsecuring members, or the FTA digital model with securing members. Themodifications could affect the curvature of the gingiva and/or thetopography. For example, the gingiva portion 1210 of the FTA digitalmodel 1200 can be an enlarged version of the gingiva portion in one ofthe OTA or FTA digital model(s) 700, 800, 1000, 1100. In suchembodiments, a thickness of the gingiva portion 1210 can be modified toadjust a position of one or more surfaces of the gingiva portion 1210relative to the securing portions 1202. The gingiva can be enlarged byabout 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm,about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1.0 mm,about 1.1 mm, about 1.2 mm, about 1.3 mm, about 1.4 mm, about 1.5 mm, atleast about 1.5 mm, at least about 1.4 mm, at least about 1.3 mm, atleast about 1.2 mm, at least about 1.1 mm, at least about 1.0 mm, atleast about 0.9 mm, at least about 0.8 mm, at least about 0.7 mm, atleast about 0.6 mm, at least about 0.5 mm, at least about 0.4 mess, atleast about 0.3 mm, at least about 0.2 mm, or at least about 0.1 mm.

While the gingiva portion 1210 can reflect the actual curvature andtopography of a patient's gingiva as defined in the OTA or FTA, in otherembodiments the gingiva portion 1210 can more crudely represent thegingiva. For example, in some embodiments the gingiva portion 1210 canhave the general curvature but not the surface topography of the gingivafrom the OTA or FTA digital models. In certain embodiments, the gingivaportion 1210 is not derived from the gingiva portion of any of themodels and instead is a generic structure that connects and holds therelative positions of the securing portions 1202. The gingiva portioncan also be referred to as a “body portion” herein.

Referring back to FIG. 5, the process 500 continues at block 518 withobtaining an appliance template digital model. FIG. 13 illustrates anexample of an appliance template digital model 1300, shown here in aconfiguration in which the appliance template digital model 1300 issecured to the fixture digital model 1200. In some embodiments, thetemplate model 1300 can comprise an anchor portion 1302, arm portions1304, and an attachment bar portion 1306. These components can take theform of a genericized template for an appliance that is later customizedfor a particular patient (as described in more detail below with respectto FIG. 15). For example, the anchor portion 1302 can correspond to theanchor 120 of the completed appliance, and the arm portions 1304 canserve as placeholders for the arms 130 of the completed appliance. Theattachment bar portion 1306 takes the form of a continuous stripconnecting each of the arms 130. As shown in FIG. 13, the attachment barportion 1304 can be configured to be received within the channels 1204of the securing portions 1202 of the fixture model 1200. The attachmentbar 1306 can correspond in part to portions of the attachment portions140 of the arms 130 of the completed appliance.

In various embodiments, the appliance template digital model 1300 can begenerated using surface data of the fixture model 1200. For example, theappliance template digital model 1300 can be configured to substantiallyconform to the surface of the fixture model 1200. The anchor portion1302 can correspond to a curvature and/or topography of the gingivaportion 1210 of the fixture model 1200, for example. The treatmentfixture model 1200 can be modified with respect to the OTA and/or FTAmodels (with or without securing members) by, among other things,enlarging the gingiva. As such, when the anchor portion 1302 contactsthe gingiva portion 1210 of the fixture model 1200, the anchor portion1302 may be positioned so as to be slightly spaced apart from the actualgingiva as characterized in the OTA digital model 700. In someembodiments, the appliance template model 1300 can have little to nothickness dimension, instead corresponding to a three-dimensionalsurface following a contour of the fixture model 1200. In someembodiments, the appliance template model 1300 can have at least somethickness.

In block 520, the appliance template digital model 1300 can be flattenedor otherwise manipulated to generate a planar appliance template model1400 (FIG. 14). The planar template model 1400 can characterize theappliance template in a 2D or substantially planar data configuration.In some embodiments, the planar appliance template digital model 1400corresponds to or is at least derived from the contoured appliancetemplate model 1300. For example, the appliance template digital model1300 (FIG. 13) can be converted into the planar appliance template model1400 (FIG. 14) by flattening, planarizing, or otherwise converting thedigital model 1300 to generate the planar appliance template model 1400.Such conversion may be carried out using a processor system andappropriate software such as, but not limited to ExactFlat®,Solidworks®, Autodesk® Inventor, Creo®, or other suitable software.

At block 522, the planar appliance digital model is obtained. An exampleof a planar appliance model 1500 is shown in FIG. 15. In this stage, theparticular shape and configuration of the arms of the appliance can bedetermined, such as by modifying or substituting portions or componentsof the planar template model 1400 (FIG. 14). For example, the particulardimensions, geometry, and material properties of arms of the appliancecan be selected so as to apply the necessary force and/or torque toachieve the desired displacement determined at block 512. In someembodiments, a pre-populated library of arm designs can be used toselect an appropriate design and configuration to achieve the desireddisplacement. In some embodiments, the arm designs in the pre-populatedlibrary can be analyzed using finite element analysis (FEA) or othertechniques to determine the spring force such arms would apply whendeflected by particular amounts (e.g., the amount of deflection betweenthe FTA (when the arm is at rest) and the OTA). In some embodiments,fully or partially automated selection of particular arm designs can bereviewed and/or modified by an operator based on relevant criteria. Forexample, if the proposed arm designs include overlapping or otherwiseinterfering arms, the operator may manually adjust the shape and/orconfiguration of the arms.

Based on the determined displacement, the required forces and/or torquesrequired to move each tooth from the OTA to the FTA can be determined.The forces required to move teeth are generally in the range ofcentiNewtons, and distances moved are typically in the range ofmillimeters. The amount of moment (Newton-millimeter) acting to rotate atooth can be found by multiplying the magnitude of the applied force bythe force arm. In general, the displacement can be a 3D tooth movementthat combines both translational and rotational motion.

The forces and/or torques required to achieve the FTA may depend on thepatient's anatomy, for example the size of the particular tooth beingmoved, the anatomy of the root, etc. The forces and/or torques may alsodepend on other physiological parameters (e.g., bone density, biologicaldeterminants, sex, ethnicity, jaw (maxilla or mandible), mechanicalproperties of surrounding tissues (lips, tongue, gingiva, and bone)around the moving tooth, etc.). The particular force and/or torqueapplied to a given tooth will also depend on the particular positioningof the securing member (e.g., bracket). For example, a securing memberpositioned further off a center-of-resistance of a tooth will generatemore torque under a given applied force than a securing member that ispositioned nearer to a center-of-resistance of the tooth. Based on thedesired displacement (e.g., along six degrees of freedom), the patient'sanatomy, and the location of the securing member, a particular armconfiguration can be selected to generate the desired force and/ortorque on the subject tooth, so as to move the tooth from the OTA to theFTA. By determining appropriate thickness, widths, shapes, andconfigurations of the arms and other components of the orthodonticappliance, an appliance configuration that applies forces and torques tothe appropriate teeth to move the teeth to the FTA is determined.

In particular examples, the design of the appliance may be performed byan operator, with the processor system and appropriate design softwaresuch as, but not limited to CAD software such as, but not limited toSolidworks®, Autodesk® Inventor, Creo®, or the like. FEA software suchas, but not limited to Abaqus, Ansys, etc. may be employed to design thesprings and arms in order to apply the desired or optimal force to theteeth. For example, such software and processing systems may be employedto design and alter the thickness, cut width, length, as well as theoverall design of each arm based at least in part on the movement of thetooth to which the arm is connected.

In some examples, if a tooth needs to be displaced by a longer distanceor the tooth is smaller (e.g. lower incisors), the arm 130 may bedesigned such that it is more flexible. In some embodiments, theselection or design of the arms 130 can account for variation in therate of teeth movement based on direction. It is known that the rate oftooth movement when a given force is applied to the tooth is differentdepending on the direction of movement. For example, extrusion is thefastest movement for a given force, intrusion is the slowest, andmesiodistal and buccolingual movements are somewhere in between thesetwo extremes. In one example, if a tooth moves 2 mm per month occlusallyand 1 mm per month distally under the same applied force, the tooth willnot move in a straight line as the occlusal movement will be more rapidthan the distal movement. The occlusal movement will finish first, andthen the tooth will move in a straight line from there in the distaldirection until that motion is complete. It may be desired to move thetooth in a particular trajectory, and so the force applied distally canbe different from the force applied occlusally. For example, it may bedesired to move the tooth in a straight line, and so the distal forcewould have to be greater than the occlusal force in order to result in astraight trajectory from OTA to FTA.

In some embodiments, the arms 130 can be designed to impart less forceon some or all of the teeth because of periodontal problems such as boneresorption, root resorption or attachment loss. The ability to customizethe force or torque (or both) applied to each tooth can providesignificant advantages over traditional orthodontics. In particularexamples, the computer-aided procedure employs an algorithm forselecting or configuring an arm or other feature of an appliance, forexample, from one or more predefined sets of options or one or moreranges of options. Thus, for example, a set of options or a range ofoptions may be predefined for one or more parameters associated with anarm or other feature.

The one or more parameters associated with an arm 130 may include, butare not limited to, the overall length of the arm, the shape orconfiguration of the biasing portion 150, the shape or configuration ofthe attachment portion 140, the width dimension of one or more sectionsof the arm 130, the thickness dimension of one or more sections of thearm 130, or the like.

Obtaining the planar appliance digital model 1500 can also includedetermining the shape and configuration of the anchor 120. For example,the anchor 120 can be selected so as to substantially conform to thepatient's gingiva without impinging thereon. The thickness, depth, orother properties of the anchor 120 can also be selected to providesufficient rigidity against the forces generated by the arms. In someembodiments, the anchor 120 design can be automatically generated (e.g.,by being automatically generated to substantially conform to thepatient's gingiva or other location in the FTA model (e.g., model 1100)or the OTA model (e.g., model 700 or 1000). In some embodiments, anoperator may manually select or revise the design and configuration ofthe anchor as desired.

Although in the illustrated embodiment, the specific features of thearms 130 are selected while the appliance model is in a substantiallyplanar or 2D form, in other embodiments the appliance features can beselected and configured based on a digital model that is contoured tocorrespond to a patient's anatomy. For example, the 3D appliancetemplate model 1300 (FIG. 13) can be modified to select particular arms130, anchor 120, or any aspects thereof to achieve the desiredappliance. In some embodiments, the template is omitted altogether, anda customized appliance model is generated based on the OTA model and/orthe FTA model without the use of an intervening template model.

In some embodiments, the planar appliance model 1500 can be 2D, suchthat the model defines no thickness of the appliance. Such a model canbe used, for example, to cut an appliance out of a sheet of material. Insuch cases, the thickness can be determined by selecting the sheet ofmaterial and by polishing, etching, grinding, deposition, or othertechniques used to modify a final thickness of the appliance. In someembodiments, the planar appliance model 1500 can define a thicknessdimension while remaining substantially planar or flat. For example, theplanar appliance model 1500 can define a thickness of the appliancewhich may be uniform or may vary across some or all of the anchor 120and arms 130.

In some embodiments, a 3D or contoured appliance model can be generated,for example by manipulating the planar appliance model 1500 into acurved or contoured configuration. In some embodiments, the 3D appliancemodel can correspond to the appliance mounted to the teeth in the OTA(e.g., by manipulating the planar appliance model 1500 using positiondata of the securing members 900 in the OTA model 1000 (FIG. 10), or bymanipulating the planar appliance model 1500 using position data of thesecuring members 900 in the FTA model 1100 (FIG. 11)).

With reference to blocks 516, 518 and 520 together, in some examples acomputer-aided procedure can be used to select or determine the shapeand configuration of the arms, anchor, and/or any other features of anappliance. The procedure may be configured to select one (or more thanone) arm, securing member, anchor, or parameter thereof, or any otheraspect of the appliance based on one or more input data. For example,input data may include, but is not limited to, a type of a tooth (e.g.,molar, canine, incisor, etc.) or a size of a tooth. A larger tooth (suchas a molar) may require larger arms or larger, wider or thicker loop orcurved features for providing a greater force, than for a smaller tooth(such as an incisor). Additionally or alternatively, input data mayinclude the size of the periodontal ligament (PDL) of one or more teeth.The size of the PDL may be obtained by any suitable process including,but not limited to, CBCT scan or other imaging technique. Other inputdata may include, but is not limited to, the number or direction offorces to be applied to a tooth or teeth in a three-dimensional space.For example, a desired tooth movement direction may require one or moreshapes or configurations of arms that differ from the shapes orconfigurations required for a different tooth movement direction. Otherinput data may include but is not limited to, the number or direction ofrotational forces (or torque) to be applied to a tooth or teeth. Forexample, a desired tooth movement in a rotational direction may requireone or more shapes or configurations of arms that differ from the shapesor configurations required for a different tooth movement direction.Additionally, in some embodiments two or more arms can be attached to asingle tooth, either with each arm coupled to a separate securingmember, or with two arms coupled to the same securing member. In suchinstances, the input data can include a number of arms and/or securingmembers coupled to each tooth, or alternatively the number of armsand/or securing members can be generated as output data.

In some embodiments, this computer-aided procedure can include analgorithm that includes, as input, (but is not limited to) one or morevalues representing one or more of: (a) up to three translational and upto three rotational movements from an OTA to an ITA or FTA, or from anITA to another ITA or FTA; (b) the surface of periodontal ligament (PDL)or the area of the root of a or each tooth; (c) bone density of thepatient; (d) biological determinants for example, obtained from saliva,gingival fluid (GCF), blood, urine, mucosa, or other sources; (e) genderof the patient; (f) ethnicity of the patient; (g) the jaw (maxilla ormandible) for which the appliance is to be installed; (i) the number ofteeth on which the appliance is to be installed; and (j) mechanicalproperties of the tissue (lips, tongue, gingiva) and bone around theteeth to be moved. In various embodiments, one or more of such inputscan affect the forces (e.g., magnitude, direction, point of contact)required to move each tooth from the OTA to or toward the FTA.

In other examples, other suitable input data may be employed. Thecomputer-aided process employs a computer programed or configured withsuitable non-transient software, hardware, firmware, or combinationsthereof, to generate an output (such as one or more selected armconfigurations, anchor configurations, or securing memberconfigurations), based on the one or more input data.

An output generated by the computer-aided procedure, based on suchinput, can include, but is not limited to one or more of: (a) a designof an arm; (b) a width or cut-width of one or more of such arms; (c) athickness dimension of any portion of the appliance of the entireappliance; (d) mechanical properties of such arms including but notlimited to amount of flexibility, or a magnitude of bias force orresilience; (e) a design of an anchor; (f) a width or thickness of theanchor; (g) connection locations between the arms and the anchor; and/or(h) transformational temperature of the nitinol (or other material) inone or more (or each) section of the appliance. As noted previously, insome embodiments the output can include particular configurationsselected from among a pre-populated library of anchors and/or arms. Forexample, based on the inputs, a desired force (e.g., magnitude anddirection) can be determined for each tooth. Based on the desired force,an appropriate anchor member and/or arm configuration can be selectedthat provides the desired force or a suitable approximation thereof. Insome embodiments, the configuration of the appliance (including any ofthe outputs listed above) can be generated independently of anypre-populated library. In some embodiments, generating the output caninclude analyzing provisional selections or designs using finite elementanalysis (FEA) or other techniques to determine performance parameters,for example, the spring force such arms would apply when deflected byparticular amounts (e.g., the amount of deflection between the FTA (whenthe arm is at rest) and the OTA).

In particular examples, computer-aided processes can be employed to makecustomized appliances, for each given patient. In other examples,appliances may be made in a plurality of predefined sizes, shapes,configurations, or the like, based on a population group. Accordingly, adifferent semi-customized size, shape or configuration would beconfigured to fit each different selected portion of the populationgroup. In that manner, a more limited number of different appliancesizes, shapes and configurations may be made to accommodate a relativelylarge portion of the population.

Based on the determined shape and configuration of the arms and theanchor, the full appliance shape data can be generated. In someembodiments, the appliance shape data can take the form of 3D data(e.g., the appliance in its shape-set form following heat treatment orother suitable setting technique) or planar or substantially 2D data(e.g., the appliance in its laid-flat form, for example as cut out froma sheet of material).

At block 524, an appliance can be fabricated (e.g., based on the planarappliance digital model 1500 (block 520). And at block 526, a fixturecan be fabricated (e.g., based on the fixture digital model 1200 (block516). Fabrication of the fixture and the appliance are described in moredetail below.

Methods of Fabricating Orthodontic Appliances

As noted above, one or more digital models can be generated thatcharacterize or define an appliance (e.g., the planar appliance digitalmodel 1500, or a contoured appliance digital model). In variousembodiments, one or more such digital models can be used to fabricate anappliance for use in a patient. FIG. 16 illustrates an example of anappliance 100 fabricated using one or more of the digital modelsdescribed herein. Certain example fabrication processes are describedbelow. However, one of skill in the art will appreciate that anysuitable fabrication process may be used to manufacture appliances (orcomponents thereof) as disclosed herein.

In some embodiments, an orthodontic appliance 100 can be fabricatedusing a planar digital appliance model (e.g., the planar appliancedigital model 1500). For example, the planar appliance digital model caninclude planar or substantially 2D shape data. The planar shape data canbe provided to a suitable fabrication device (such as, but not limitedto one or more machines that perform cutting, laser cutting, milling,chemical etching, wire electrical discharge machining (EDM), waterjetting, punching (stamping), etc.) for cutting a flat sheet of materialinto a member having a shape corresponding to the planar appliancedigital model 1500. The member may be cut from a flat sheet of anysuitable material, such as, but not limited to Nitinol, stainless steel,cobalt chrome, or another type of metal, a polymer, a superelasticmaterial, etc. The sheet of material can have a thickness selected toachieve the desired material properties of the resulting member. Invarious embodiments, the thickness of the sheet of material can beuniform or can vary (e.g., along a gradient, being thinned at particularregions using etching, grinding, etc., or thickened at particularregions using deposition, etc.). In some examples, the sheet can have athickness of between about 0.1 mm and about 1.0 mm, between about 0.2 mmand about 0.9 mm, between about 0.3 mm and about 0.8 mm, between about0.4 mm and about 0.7 mm, or about 0.5 mm. In some embodiments, the sheetcan have a thickness of less than about 1.5 mm, less than about 1.4 mm,less than about 1.3 mm, less than about 1.2 mm, less than about 1.1 mm,less than about 1.0 mm, less than about 0.9 mm, less than about 0.8 mm,less than about 0.7 mm, less than about 0.6 mm, less than about 0.5 mm,less than about 0.4 mm, less than about 0.3 mm, less than about 0.2 mm,or less than about 0.1 mm.

Next, the cut member can be bent from its substantially planar form intoa contoured arrangement. FIG. 16 illustrates an example of a completedappliance 100 resulting from such bending of a planar member. Asillustrated, and as described elsewhere herein, the appliance 100 caninclude an anchor 120 and a plurality of arms 130 extending away fromthe anchor 120. Each arm 130 can include an attachment portion 140configured to mate with a securing member adhered to a patient's tooth,and a biasing portion 150 disposed between the attachment portion 140and the anchor 120. When the appliance 100 is installed in the patient'smouth, each of the arms 130 can connect to a different one of the teethto be moved and exerts a specific force on its respective tooth, therebyallowing an operator to move each tooth independently.

In some embodiments, the planar member, after being cut from a sheet orotherwise formed, may be bent or otherwise manipulated into a shape orcontour corresponding or substantially corresponding to the FTAconfiguration. For example, the member can be a shape cut from a flatsheet of Nitinol or other suitable material and assume a generallyplanar configuration. The member can be bent into a desired 3D orcontoured configuration, for example corresponding to the contouredappliance digital model 1600. In certain examples, one or more fixturesare configured for use in bending the planar member into the desired 3Dshape. In such examples, after cutting the planar member, the planarmember can be fixed on or between one or more fixtures and bent orotherwise manipulated to form a desired 3D shape. In some embodiments,either before or after cutting the member from the sheet, the thicknessof the member can be modified at least in some portions to achievedesired material properties. For example, the thickness of the membercan be reduced in at least some regions using grinding, chemicaletching, photoetching, electrical discharge machining, or any othersuitable material removal process. The thickness of the member can beincreased in at least some regions using thin film deposition,electroplating, or any other suitable additive technique. In someembodiments, the planar member can be formed using 3D printing or othertechnique instead of or in addition to cutting the planar member from asheet of material. 3D printing may provide certain advantages, forexample ease of controlling the thickness of different portions of theappliance. In some embodiments, the planar member can be formed by 3Dprinting metal, a polymer, or any other suitable material amendable toadditive manufacturing by 3D printing.

In some embodiments, the appliance can be shape set into the desiredcontoured or 3D configuration (e.g., corresponding to the OTA, the FTA,the fixture, etc.). One or more shape setting procedures, such as, butnot limited to heat treatment, may be applied to the appliance whileheld in the desired 3D shape, during or after the bending operation, toset the desired 3D shape. A shape setting procedure involving a heattreatment may include rapid cooling, following heating of the memberduring or after bending. Additional details regarding example heattreatment and associated fixtures are described below.

By employing a cut planar member, instead of a traditionalsingle-diameter wire, a greater variety of resulting 3D shapes may bemade, as compared to shapes made by bending single-diameter wire. Thecut planar member may have designed or varying widths and lengths that,when bent into a desired shape, can result in portions of the 3Dappliance having variances in thickness, width and length dimensions. Inthis manner, the planar member can be cut into a shape that provides adesired thickness, width and length of biasing portions, arms, or othercomponents of the appliance. A larger variety of shapes may be providedby bending a custom cut planar member, as compared to bending asingle-diameter wire.

In some examples, the entire appliance (including arms and anchor) isfabricated by bending the cut planar member into the desired 3D shapedmember. In other examples, additional components may be attached to the3D shape, for example, after bending. Such additional components mayinclude, but are not limited to attachment portions 40, biasing portions150, arms 130, etc. Such additional components may be attached to the 3Dshaped member by any suitable attachment mechanism including, but notlimited to, adhesive material, welding, friction fitting, etc.

In some embodiments, the appliance can be 3D printed directly into thedesired contoured or 3D shaped configuration. In some embodiments, the3D shaped member can be 3D printed, for example using any suitablematerial. In cases in which the appliance is 3D printed using Nitinol,there may be no need for a shape-setting process (e.g., heat treatment).Additionally, 3D printing may allow the use of different geometries(e.g., a cross-sectional shape of the anchor member may be oval, ratherthan rectangular, which may increase patient comfort on both thegingival-facing and lingual-facing sides of the anchor).

Methods of Shape-Setting Orthodontic Appliances

In various embodiments of the present technology, a physical fixture foruse in manufacturing of an orthodontic appliance can be fabricated basedon a fixture digital model (such as fixture digital model 1200). Thefixture can be used to shape-set the appliance. For example, theappliance can be manufactured in a planar configuration (e.g., cut froma sheet of material, 3D printed, etc.). The appliance can then bemanipulated into a desired 3D configuration by securing and/orconforming the appliance to the fixture. The appliance and fixture canundergo a shape setting process while the appliance is retained in thedesired 3D configuration by the fixture such that, when the appliance isseparated from the fixture, the appliance retains the desired 3Dconfiguration. In some embodiments, the appliance can be manufactured ina non-planar, first 3D configuration and manipulated into a desiredsecond 3D configuration (different than the first 3D configuration) bysecuring and/or conforming the appliance to the fixture.

FIG. 17 illustrates an example of a fixture 1700 configured to retain apre-installation version of the appliance in a desired configurationduring a shape setting procedure. The fixture 1700 can be configured tohold a pre-installation version of the appliance in a configurationcorresponding to an intended configuration of the appliance when theteeth are in the FTA. When the appliance is removed from the fixtureafter the shape setting procedure, the appliance is biased to maintainits shape corresponding to the FTA. When the appliance is installed inthe patient's mouth in the OTA, the appliance is deformed. Because theappliance is biases to maintain its shape corresponding to the FTA, itwill tend to return from a deformed configuration to its intendedconfiguration, and thus will urge the teeth toward their desired, finalpositions.

The fixture 1700 can be manufactured based on the fixture digital model(e.g., the fixture digital model 1200 (FIG. 12)). For example, thefixture digital model or associated data can be provided to afabricating system to produce a physical fixture based on the fixturedigital model. In one example, the fixture data can be used to 3D printa model of the fixture in wax. The wax model may then be used toinvestment cast the fixture in brass or other suitable material. In someembodiments, the fixture can be 3D printed directly in brass or othersuitable material (e.g., stainless steel, bronze, a ceramic or othermaterial that tolerates high temperatures required for heat treatment).

As shown in FIG. 17, the fixture 1700 can comprise one or more securingportions 1702 and a gingiva portion 1710. The securing portions 1702 canextend away from the gingiva portion 1710. The securing portions 1702can be configured to releasably retain one or more portions of anappliance at a specific location relative to other portions of theappliance. For example, the securing portions 1702 can be configured toretain attachment portions (e.g., attachment portions 140, etc.) of anappliance during a shape setting procedure in positions corresponding tointended positions of corresponding securing members when the applianceis later installed in the patient's mouth and the securing members aresecured to the patient's teeth (for example, when the teeth, and thussecuring members, are in an OTA or FTA). In some embodiments, thesecuring portions 1702 are positioned relative to one another and to thegingiva portion 1710 to reflect the positions of the teeth in the FTA.In other embodiments, the securing portions 1702 are positioned toreflect the teeth in the OTA or an ITA.

The securing portions 1702 can have a geometry configured to facilitatepositioning and/or retaining corresponding attachment portions at theintended positions. For example, as shown in FIG. 17, the securingportions 1702 can define first channels 1704 and second channels 1706angled with respect to the first channels 1704. The first and secondchannels 1704, 1706 are configured to receive attachment portions of anappliance at least partially therein to locate the attachment portionsat their intended positions. The securing portions 1702 can compriseprotrusions (e.g., protrusions 1708) extending away from thecorresponding securing portion 1702 and defining channels. In someembodiments, the protrusions 1708 define the first and second channels1704, 1706 and/or the protrusions 1708 can define third channelsconfigured to receive a fastener at least partially therein. Forexample, an elongate member such as a ligature wire can be wound aboutone of the securing portions 1702 and an attachment portion of anappliance such that the ligature wire is positioned within channelsdefined by the protrusions 1708 and secures the attachment portion tothe securing portion 1702. The securing portions 1702 can be configuredto receive and/or coupled with other fasteners, such as ties, sutures,bands, clasps, and others. In various embodiments, the securing portions1702 can define one or more through-channels, apertures, or otheropenings to facilitate securing of an attachment portion to the securingportion 1702 via a fastener. For example, such openings can allow apushing tool to be inserted from the back of the securing portion 1702(e.g., through the buccal surface of the fixture 1700) to push anattachment portion away from the securing portion 1702 after the heattreatment has been completed and the ligature wire or other fastener hasbeen removed.

The gingiva portion 1710 of the fixture 1700 comprises the shape ofgingival tissue and provides a surface on which a portion of theappliance is conformed during a shape setting procedure. Because thefixture 1700 is based on the fixture digital model 1200, the gingivaportion 1710 may be substantially identical to the gingiva portion 1210of the fixture model 1200, which may be substantially identical to thegingiva portion from any of the OTA or FTA digital models (e.g., 700,800, 1000, 1100). For example, it can be desirable to use the gingivaportion 704 from the OTA digital model 700 for the gingiva portion 1210of the fixture model 1200 to prevent or limit impingement of thepatient's gingiva by an appliance installed in the patient's mouth andhaving a shape corresponding to a shape of the fixture 1700. In somecases, the securing portions 1202 can be positioned to reflect the teethin the FTA while the gingiva portion 1210 reflects the gingiva in theOTA.

Additional details regarding fixtures and components thereof arediscussed below with reference to FIGS. 33A-34B, for example.

As shown in FIG. 18, a pre-installation version of the appliance can bepositioned on and secured to the fixture 1700. The combined assembly1800 thus includes an appliance 100 that has been bent or otherwisemanipulated into shape against a surface of the fixture 1700. Theappliance 100 can be secured to the fixture 1700 by placing attachmentportions into the securing portions 1702 of the fixture. Fasteners 1802(e.g., ties, ligature wires, sutures, bands, wraps, etc.) can be wrappedaround the appliance 100 at a plurality of positions to secure theappliance 100 with respect to the fixture 1700. Next, the shape settingprocedure is performed shape set the appliance 100, after which theappliance 100 can be removed from the fixture 1700.

Some examples of a shape setting procedure can include heating theappliance 100 to a selected temperature (such as, but not limited to 525degrees centigrade) for a selected period of time (such as, but notlimited to 20 minutes), followed by rapid cooling. The rapid cooling canbe achieved by any suitable cooling procedure such as, but not limitedto water quench or air-cooling. In other examples, the time andtemperature for heat treatment can be different than those discussedabove, for example, based upon the specific treatment plan. For example,heat treatment temperatures can be within a range from 200 degreescentigrade to 700 degrees centigrade and the time of heat treatment canbe a time in the range up to about one hundred and twenty minutes. Inparticular examples, the heat treatment procedure may be carried out inan air or vacuum furnace, salt bath, fluidized sand bed or othersuitable system. After completing the heat treatment, the appliance hasa desired 3D shape and configuration (e.g., corresponding substantiallyto the fixture and/or to the desired FTA). In other examples, othersuitable heat-treating procedures may be employed including, but notlimited to resistive heating or heating by running a current though themetal of the appliance structure. In some embodiments, the shape settingprocedure does not rely on heat.

One or more additional post processing operations may be provided on the3D shaped article, including, but not limited to abrasive grit blasting,shot peening, polishing, chemical etching, electropolishing,electroplating, coating, ultrasonic cleansing, sterilizing or othercleaning or decontamination procedures.

In examples in which the appliance is made of multiple components, some(or each) of the components of the appliance may be made according tomethods described above, and then connected together to form the desired3D appliance configuration. In these or other examples, the appliance(or some or each component of the appliance) may be made in othersuitable methods including, but not limited to: directly printing ofmetal, first printing of a wax member and then investment casting thewax member into a metal or other material, printing of elastomericmaterial or other polymer, cutting or machining out of solid material,or cutting the components out of a sheet of metal and shape setting intothe desired 3D configuration.

As discussed herein, one or more fixtures may be configured for use inbending a cut planar member into a desired 3D shape configuration. Inparticular examples, one or more fixtures are provided (such as, but notlimited to, custom made) for each jaw of a patient. For example, thefixtures may be customized in shape and configuration for each patientand can be made in any suitable manner, including molding, machining,direct metal printing of stainless steel or other suitable metals, 3Dprinting of a suitable material, such as, but not limited to stainlesssteel via powder bed fusion, or a steel/copper mix via binder jetting,as well as first printing the configuration in wax and then investmentcasting the wax into various metals. In various examples describedherein, the fixtures may be configured of material that is sufficientlyresistant to the temperature of the heat treatment. In particularexamples, one or more robots may be employed with or without the one ormore fixtures, for bending the cut planar member into a desired 3D shapeconfiguration.

In some embodiments, a single shape-setting step may be completed todeform the member from its planar configuration to its desired 3Dconfiguration. However, in certain embodiments the shape setting mayinclude two or more shape-setting steps (e.g., two or more heattreatment processes, potentially using two or more different fixtures).In such cases, the amount of deformation imparted to the appliancewithin each shape-setting step may be limited, with each subsequentshape-setting step moving the appliance further toward the desired 3Dconfiguration.

The completed appliances can then be sent (optionally along with bondingtrays and/or securing members) to the treating clinician. To install theappliances, the orthodontist can clean the lingual side of the patient'steeth to prepare them for bonding (e.g., with pumice powder). Thesurface of the teeth can then be sandblasted (e.g., with 50-micronaluminum oxide). The securing members can then be attached using abonding tray as described elsewhere herein.

After the appliances are fabricated and the securing members areattached to the teeth, each arm can be coupled to its correspondingsecuring member element to install the appliance. Once installed, theappliance imparts forces and torques on the teeth, to move the teeth tothe desired FTA. After treatment is completed (e.g., OTA to FTA, OTA toITA, ITA to ITA, or ITA to FTA) the arms may sit passively in thesecuring members and force will no longer be applied to the teeth.Alternatively, any remaining force applied by the arms may fall below athreshold for causing further displacement of the teeth.

The patient can return for a check-up appointment (e.g., atapproximately 2-3 months), and if the treatment is advancing as planned,nothing is done until the patient returns at a planned time forappliance removal. At this stage the securing members may be removed. Iftreatment is not progressing as planned, the appliance may be removed,the patient's mouth rescanned, and a new appliance can be devicedesigned and installed based on a modified treatment plan.

IV. Selected Embodiments of Methods of Orthodontic Treatment

FIG. 19 is a flow diagram of an example process 1900 of orthodonticallytreating a patient in accordance with several embodiments of the presenttechnology. As shown in FIG. 19 and described in greater detail herein,the process 1900 can include obtaining tooth movement datacharacterizing movements of the patient's teeth to be accomplishedduring the orthodontic treatment (process portion 1902). The toothmovement data can characterize a movement (or lack thereof) of each ofthe patient's teeth from an original position of the tooth to a desired,final position of the tooth. In some embodiments, obtaining the toothmovement data comprises identifying, evaluating, and/or modifying one ormore of the tooth movements. The process 1900 can also include obtaininga treatment plan (process portion 1904), which may include an indicationand/or a suggestion of one or more orthodontic interventions to beemployed to accomplish the tooth movements, a design of an appliance orother intervention configured to accomplish the tooth movements, and/orother useful information regarding the planned treatment (e.g., anestimated duration of the treatment, a complexity of the treatment,etc.). At process portion 1906, the treatment plan and/or the toothmovement data can be communicated to any one stakeholder or combinationof stakeholders involved in the orthodontic treatment. Such stakeholdersmay include, but are not limited to, a technician designing anorthodontic appliance, an orthodontist, a patient, and/or others. Thetreatment can be implemented at process portion 1908 according to thetreatment plan. In some embodiments, the treatment is evaluated (processportion 1910) during and/or after implementation of the orthodontictreatment, which can comprise comparing actual positions and/ormovements of the patient's teeth to planned positions and/or movementsof the teeth. The evaluation can be used in assessing treatmentoutcomes, determining if further treatment is necessary, selecting anddesigning orthodontic interventions to accomplish further treatment,etc. As shown in FIG. 19, the process 1900 can repeat based on theevaluation. For example, if a first treatment is evaluated at the end ofthe first treatment and it is determined that further treatment isnecessary, process portion 1902 can be repeated to obtain new movementdata characterizing movements of the patient's teeth from the actualpositions to the desired, final positions, process portion 1904 can berepeated to obtain a new treatment plan, etc.

All or a portion of the process 1900 can be iterative. For example, theprocess 1900 can include evaluating and/or modifying the output at anygiven stage, such as the tooth movement data and/or the treatment plan.Evaluation of the movement data and the treatment plan can bequalitative or quantitative. In any of the examples herein and others,evaluating and/or modifying the movement data and/or the treatment plancan be performed manually (e.g., by a human operator) and/orautomatically (e.g., by suitable software).

The following discussion expands on several aspects of the process 1900.

A. Obtaining Tooth Movement Data

The process 1900 of orthodontically treating a patient includesobtaining tooth movement data characterizing desired movements of thepatient's teeth (process portion 1902). FIG. 20 is a flow diagram of anexample process 2000 for obtaining such tooth movement data. The process2000 can include obtaining OTA data characterizing original positions ofthe patient's teeth (process portion 2002). In some embodiments, theprocess 2000 includes obtaining clinical instructions (process portion2004). As described in greater detail below, the clinical instructionscan provide useful information regarding the orthodontic treatment suchas the types of interventions to be used, clinical objectives and/orpriorities for the treatment, etc. From the OTA data and/or the clinicalinstructions, the process 2000 can include obtaining first FTA datacharacterizing final positions of the patient's teeth (process portion2006). From the OTA data and the first FTA data, the process 2000 caninclude obtaining overall movement data characterizing overall movementsof the patient's teeth from the original positions to the finalpositions (process portion 2008). An overall movement of one of apatient's teeth can comprise zero, one, two, or three translationaldisplacements and zero, one, two, or three rotational displacements. Theoverall movement comprises a transformation that, when applied to atooth, would move the tooth from its original position to its finalposition.

As shown in FIG. 20, the process 2000 can include determining whether toperform an arch registration (process portion 2010). In its simplestform, an arch registration process compares both of the patient's dentalarches as a single unit in the OTA to both arches as a single unit inthe FTA and identifies a common movement of both arches. In someembodiments, the arch registration process also eliminates the commonmovement.

The arch registration can be beneficial for identifying, evaluating,and/or modifying the positions of the patient's dental arches in thefirst FTA to facilitate coordination of the orthodontic treatment,ensure that the movements of the arches are achievable, reduce thetreatment time, etc. For example, a temporary anchorage device (TAD) orsurgery can be employed to move all of the patient's teeth in both ofthe patient's dental arches in the same direction according to the sametransformation. Conversely, such movements may not be possible withother interventions such as appliances, elastics, or others.Accordingly, if the clinical instructions indicate that surgery or TADsare not an option, it might not be appropriate for tooth movements toindicate that both dental arches should be moved in the same directionaccording to the same transformation. In these and other embodiments, anarch registration can be performed (process portion 2012) to modify thepositions of the dental arches in the first FTA. However, if theclinical instructions indicate that TADs or surgery are an option,movement of both arches may be appropriate and the result of thedecision at process portion 2010 is that an arch registration should notbe performed. In some embodiments, the arch registration is performedregardless of the clinical instructions.

If the result of the decision at process portion 2010 is that an archregistration should be performed, the process 2000 can proceed toperforming the arch registration at process portion 2012. Performing thearch registration can include registering the first FTA data to the OTAdata to obtain first outputs 2014, which include second FTA data,“purple movement” data, and/or “orange movement” data. As used herein,“purple movements” refer to a movement of all of a patient's teeth inboth of the patient's dental arches according to the sametransformation. Also as used herein, “orange movements” refer to amovement of all of a patient's teeth in one of the patient's dentalarches according to the same transformation.

After performing the arch registration at process portion 2012, theprocess 2000 proceeds to performing a tooth registration (processportion 2016). Alternatively, the process 2000 can proceed to performinga tooth registration (process portion 2016) directly after processportion 2010 if the result of the decision is that an arch registrationshould not be performed. If an arch registration was performed,performing the tooth registration can comprise registering the secondFTA data to the OTA data. If an arch registration was not performed,performing the tooth registration can comprise registering the first FTAdata to the OTA data. The tooth registration can be performed to obtainsecond outputs (process portion 2018) including ITA data, orangemovement data, and/or blue movement data. As used herein, “bluemovements” refer to a movement of at least one tooth in one dental archof a patient relative to other teeth in the same dental arch. The ITAdata can characterize positions of the teeth in one of the patient'sdental arches after the teeth have been moved from their originalpositions according to the blue movement data. If there are no orangemovements, then the ITA data corresponds to the FTA data (e.g., thefirst FTA data if no arch registration was performed, the second FTAdata if an arch registration was performed, etc.).

1. Obtaining OTA Data

Obtaining OTA data characterizing original positions of a patient'steeth (process portion 2002) can be performed as described elsewhereherein. The OTA data can comprise one-dimensional coordinates,two-dimensional coordinates, three-dimensional coordinates, orhigher-dimensional coordinates. In some embodiments, the OTA datacharacterizes one original position of each tooth. Additionally oralternatively, the OTA data can characterize multiple original positionsof each tooth. For example, the OTA data can characterize the originalpositions of multiple locations on each tooth. In some embodiments, theOTA data characterizes original positions of only some of the patient'steeth.

The OTA data can be obtained prior to suggesting and/or implementing anorthodontic intervention. In some embodiments, the OTA data can beobtained when the teeth are maloccluded, mis-aligned, crowded, orotherwise in need of orthodontic correction. For example, the OTA datacan be obtained when the teeth are in an original arrangement. The OTAdata can be obtained by scanning the patient's teeth. For example, asshown in FIG. 6, the OTA data can be obtained by scanning the patient'steeth using an intraoral optical scanner. The scanning can be performedusing any suitable technique, for example dental cone beam CT scanning,magnetic resonance imaging (MRI), or similar device or technique. Invarious examples, the OTA data can include data associated with theroots of the teeth as well as the exposed portions. In some examples,the OTA data can be obtained using an impression made of the patient'supper and/or lower jaws (e.g., using polyvinyl siloxane or any othersuitable impression material). The impression can then be scanned tocreate 3D data, which can include the relationship between the upper andlower jaw (e.g., to record the patient's bite). In examples in whichimpressions are used, the relationship between the teeth in the upperand lower arches (inter-arch relationship) can be obtained by taking awax bite of the patient in the centric position. In various embodiments,the OTA data can be obtained directly (e.g., by imaging the patient'smouth using an appropriate imaging device) or indirectly (e.g., byreceiving pre-existing OTA data from an operator or another source).

In some embodiments, the process 2000 can comprise obtaining a digitalmodel of the patient's teeth and/or other oral tissues. For example, asdetailed herein, a digital model of the patient's teeth can be obtainedthat characterizes the teeth in an original arrangement in which theteeth are maloccluded, mis-aligned, crowded, or otherwise in need oforthodontic correction. An example digital model 700 is depicted in FIG.7. In some embodiments, one or more teeth present in the originalarrangement may be designated for extraction prior to use of theorthodontic appliance.

In various embodiments, obtaining the digital model corresponding to theOTA data can include first obtaining a single complex 3D database of thepatient's jaw, which is then segmented to separate the patient's teethinto separate 3D bodies (e.g., individual teeth or blocks of multipleteeth) that can then be manipulated virtually by an operator. Suchsegmentation can be performed using any suitable techniques or software,for example using iROK Digital Dentistry Studio or other suitablesoftware. Following segmentation, the resulting 3D databases of theupper and lower teeth can include a model of the gingiva and independentmodels of each tooth. As a result, the OTA data can be manipulated by anoperator to virtually move teeth relative to the gingiva and/or eachother.

In some embodiments, obtaining the OTA data can be iterative. Forexample, obtaining the OTA data can comprise obtaining preliminary OTAdata from an intraoral scan of a patient's teeth and evaluating thepreliminary OTA data. The evaluation can assess whether the preliminaryOTA data sufficiently characterizes the patient's teeth and oral tissue,a quality of the data, etc. For example, an operator and/or suitablesoftware can review a digital model of the patient's teeth in theoriginal arrangement and identify portions (if any) with poorresolution, gaps in the model, etc. If the preliminary OTA data isacceptable and/or preferred, the preliminary OTA data can be selected asthe OTA data. If the preliminary OTA data is not acceptable and/orpreferred, the preliminary OTA data can be modified and/or newpreliminary OTA data can be obtained (e.g., via an additional scan ofthe patient's teeth) and the process 2000 can repeat.

2. Obtaining Clinical Instructions

The clinical instructions obtained at process portion 2004 can begenerated by a human operator (e.g., an orthodontist, an oral surgeon, atechnician, etc.). The instructions can include information regardingthe orthodontic treatment such as orthodontic issues to be addressed(e.g., malocclusions, misalignments, etc.), desired final positions ofthe teeth, desirable or undesirable movements of the teeth, orthodonticinterventions available for the treatment, requested timing of theorthodontic interventions, and/or other useful information. For example,the instructions might include that the patient will not consent toorthognathic surgery, and that the tooth movements should be able to beaccomplished by other orthodontic interventions. As examples, theinstructions might include phrases such as, but not limited to, “rotatethe central incisor,” “address class II malocclusion,” “extrude lateralincisor by 1 mm,” and/or “fix torque for lateral incisor.” Theinstructions can be provided verbally, in writing, electronically, orvia any other suitable form of communication. In some embodiments, theinstructions can be entered into suitable software on a computing deviceby a human operator. The instructions can be obtained before or afterobtaining the OTA data. In some embodiments, the instructions areobtained prior to obtaining the first FTA data, as the instructions mayfacilitate generation of the first FTA data.

3. Obtaining First FTA Data

The first FTA data obtained at process portion 2006 can be performed asdescribed elsewhere herein. The first FTA data can compriseone-dimensional coordinates, two-dimensional coordinates,three-dimensional coordinates, or higher-dimensional coordinates. Insome embodiments, the first FTA data characterizes one final positionper tooth. Additionally or alternatively, the first FTA data cancharacterize multiple final positions per tooth. For example, the firstFTA data can characterize the final positions of multiple locations oneach tooth. In some embodiments, the first FTA data characterizes finalpositions of only some of the patient's teeth. In some embodiments, thefinal positions of the teeth correspond to positions of the teeth in anoptimal or preferred arrangement (e.g., after complete orthodontictreatment) or in an intermediate arrangement (e.g., after partialorthodontic treatment).

As previously noted, in some embodiments the first FTA data can beobtained by manipulating the teeth from the original positions towardsthe final positions. In some cases, the process 2000 includes obtaininga digital model of the patient's teeth in the final positions. FIG. 8shows an example FTA digital model. Obtaining the digital model caninclude manipulating the OTA data and/or a digital model of thepatient's teeth in the original positions to virtually move teethrelative to one another, the patient's gingiva, the patient's skull,etc. When the teeth are in their final positions, they may be morealigned, less maloccluded, and otherwise aesthetically and functionallyimproved relative to the teeth in the original positions. In someembodiments, obtaining the first FTA data comprises manipulating theteeth from the original positions towards the final positions accordingto the clinical instructions. In some cases, for example whenorthognathic surgery is to be performed, obtaining the first FTA datacan comprise manipulating one or more of the patient's jaws, and therebythe teeth carried by one or more jaws.

In some embodiments, obtaining the first FTA data can be iterative. Insome embodiments, obtaining the first FTA data includes evaluatingpreliminary final positions of the patient's teeth and determiningwhether the preliminary final positions are acceptable and/or preferred.If the teeth are still maloccluded, misaligned, and/or otherwise in needof further orthodontic correction in the preliminary final positions,obtaining the first FTA data can comprise further manipulating the teethfrom the preliminary final positions towards modified final positions.As previously described with reference to obtaining the OTA data, theprocess can repeat until acceptable and/or preferred first FTA data isobtained.

In some embodiments, the first FTA data can be modified based on anocclusive contact force between the upper and lower dental arches whenthe teeth are in the final positions. If a first tooth in a maxilla of apatient contacts a second tooth in a mandible of the patient when theteeth are in an original arrangement and a human operator extrudes thesecond tooth when obtaining the first FTA, there may be undesirable andexcessive contact force between the first and second teeth. Theexcessive contact force may cause the patient's mandible to rotate aboutits condyloid processes. Rotation of the mandible about the condyloidprocesses can be predicted by an operator and/or suitable softwareand/or communicated as feedback to the operator and/or softwaregenerating the first FTA. For example, obtaining the rotation caninclude performing an algorithm to determine the rotation based on thecontact between the patient's teeth and anatomy of the patient. An axisof rotation for obtaining the rotation can be based, at least in part,on a distance between the condyloid processes of the mandible, adistance between the coronoid processes of the mandible, and/or anothersuitable anatomical distance. The axis of rotation can be obtained froma scan of the patient's jaws (e.g., via cone beam computed tomography,computed tomography, magnetic resonance imaging, etc.) or from adatabase of anthropometric measurements. For example, an averagedistance between condyloid processes for people of similar age, gender,ethnicity, etc. as the patient can be used in obtaining the axis ofrotation.

Feedback regarding the first FTA data, such as feedback regardingocclusive contact force described above, can be communicated to a humanoperator and/or suitable software involved in obtaining the first FTAdata. The first FTA data can then be modified by the operator and/orsoftware. For example, the angular displacement between the patient'smandible and maxilla can be visually communicated as an animation inwhich a software platform displays the mandible moving according to therotation. In some embodiments, the angular displacement can becommunicated as a number, a color map, and/or another suitable type ofindicia visually or audibly displayed by the software. Based on thefeedback, the first FTA data can be modified and/or specific orthodonticinterventions can be suggested. For example, a bite block could beimplemented if large occlusive contact force and rotation of themandible are predicted. As but one example, a bite block could besuggested to reduce the likelihood of debonding of a bracket if acollision is predicted between the bracket and a structure of anopposing dental arch (e.g., a tooth, another bracket, etc.).

In some embodiments, the first FTA can be obtained based on one or moreclinical considerations. For example, if the patient has mandibularanterior facial gingival recession, it may be advantageous to minimizeor limit anterior movement of the mandibular incisors during orthodontictreatment to prevent worsening of the gingival recession. Other clinicalconsiderations can include, but are not limited to, a duration of thetreatment, a comfort of the patient, a cost of the treatment, a facialstructure of the patient, etc. Such clinical considerations and othersmay be included in the clinical instructions.

FIG. 21 depicts an example of a patient's teeth in an originalarrangement 2100 and a final arrangement 2102. As shown in FIG. 21, theOTA data and the first FTA data can be obtained at one location pertooth (e.g., location 2104 a at tooth 2106 a) and/or multiple locationsper tooth (e.g., locations 2104 b—d at tooth 2106 b).

4. Obtaining Overall Movement Data

Overall movement data characterizing a movement of one or more of thepatient's teeth from an original position to a final position can beobtained at process portion 2008 using the OTA data and/or the first FTAdata. Since an overall movement of a patient's tooth from an originalposition to a final position can comprise one or more componentmovements, such as a blue movement, an orange movement, and/or a purplemovement, the overall movement data can comprise blue movement data,orange movement data, and/or purple movement data. FIGS. 22A-22F areprovided to help explain the different components.

In some embodiments, the overall movement data includes blue movementdata that represents a movement (or non-movement) of each of the teethrelative to the other teeth in the same dental arch (e.g., individualtooth movements). To illustrate, FIG. 22A shows one of a patient'sdental arches 2200 in an original arrangement and FIG. 22B shows thesame arch in an intended final arrangement. Moving the teeth in one ofthe patient's dental arches relative to the other teeth in the samedental arch can improve an alignment of the teeth in the arch. In someembodiments, such movements can change a shape of the dental arch.

In some embodiments, the overall movement data includes orange movementdata that represents a common movement of all of the teeth in one of thepatient's dental arches relative to a reference point. The commonmovement can comprise a transformation that is applied to all teeth inthe dental arch. In some embodiments, the transformation is rigid, e.g.,such that the collective structure of all of the teeth maintains itsshape and size after being transformed (e.g., distances between pointsdefining the digital models of the teeth do not change after beingtransformed). The reference point can comprise a point on the patient'sanatomy away from the arch being analyzed, such as a skull of a patient,a point on the other dental arch of the patient, etc. FIG. 22C, forexample, illustrates teeth of an upper dental arch 2200 a and a lowerdental arch 2200 b in an original arrangement and FIG. 22D illustratesthe teeth after all of the teeth in the patient's upper dental arch 2200a have been moved according to an orange movement. In this particularexample, the orange movement is a forward movement of all of the teethin the upper dental arch 2200 a relative to the lower dental arch 2200b. Moving one or more of the patient's dental arches 2200 a, 2200 baccording to an orange movement can improve a patient's occlusion (e.g.,bite). For example, the patient shown in FIG. 22C has a class IImalocclusion in which the upper dental arch 2200 a is positionedsubstantially anterior of the lower dental arch 2200 b. In FIG. 22D, thepatient's upper dental arch 2200 a and lower dental arch 2200 b arealigned such that the class II malocclusion has been treated.

In some embodiments, the overall movement data includes purple movementdata that represents a common movement of all of the teeth (i.e., theteeth in both of a patient's dental arches) relative to a referencepoint according to a common movement. The common movement can comprise atransformation that is applied to all teeth in the dental arches. Insome embodiments, the transformation is rigid. The reference point cancomprise a point on the patient's anatomy away from the dental archesbeing analyzed, such as the patient's skull or another suitablereference point. In such embodiments, neither the patient's toothalignment nor occlusion are modified. Rather, the teeth in both archesare moved according to the same transformation. For example, if thepatient's occlusion does not need modification but the patientexperiences lip drooping due to posteriorly positioned dental arches,the orthodontic treatment may include moving both of the patient'sarches anteriorly to improve the patient's facial structure. FIG. 22Eillustrates an example of a patient's upper and lower dental arches 2200a, 2200 b in an original arrangement in which the upper and lower dentalarches 2200 a, 2200 b are positioned at a first distance A1 relative toa reference point, and FIG. 22F illustrates the patient's upper andlower dental arches 2200 a, 2200 b after they have been moved away fromthe reference point by the purple movement such that the upper and lowerdental arches 2200 a, 2200 b are positioned at a second distance A2relative to the reference point.

The overall movement data can be obtained for one, some, or all of thepatient's teeth. The overall movement data can comprise one or moretranslational displacements and/or one or more rotational displacementsper tooth. For example, the overall movement data can comprise zero,one, two, or three translational displacements and zero, one, two, orthree rotational displacements per tooth. Additionally or alternatively,the overall movement data can be obtained for each location at which theOTA data and/or the first FTA data was obtained.

To further illustrate the possible different component movements of theoverall movement data, FIGS. 23A-25C schematically depict a patient'steeth in one of the patient's dental arches subject to a variety ofarrangements and movements. FIGS. 23A and 23B, for example, depictmovements 2308 of teeth in one of the patient's dental arches accordingto blue movements (e.g., individual tooth movements). As shown in FIG.23A, moving the teeth in a dental arch relative to one another cancomprise translating one or more of the teeth 2300 from the originalarrangement 2304 (teeth 2300 depicted as white boxes with dashed edges)to the final arrangement 2306 (teeth 2300 depicted as shaded boxes withsolid edges) according to movements 2308. In some embodiments, forexample as shown in FIG. 23D, moving the teeth in a dental arch relativeto one another can comprise rotating one or more of the teeth 2300 fromthe original arrangement 2304 to the final arrangement 2306 according tomovements 2308. While translation and rotation are depicted in differentschematics, it will be appreciated that the blue movements can have atranslational and/or rotational component.

FIGS. 23C and 23D depict movement of all teeth 2300 in one of apatient's dental arches according to an orange movement. Moving apatient's teeth 2300 according to a common movement can comprisetransforming each of the teeth 2300 in one of the patient's dentalarches according to the same transformation. As shown in FIGS. 23C and23D, moving all of the teeth in a dental arch from an originalarrangement 2304 (teeth 2300 depicted as white boxes with dashed edges)to a final arrangement 2306 (teeth 2300 depicted as shaded boxes withsolid edges) can comprise moving each of the teeth 2300 according to atranslational movement 2302 (see FIG. 23C) and/or moving the teeth 2300according to a rotational movement 2302 (see FIG. 23D). Such movements2302 can comprise a transformation, which can be rigid and/or affine.While translation and rotation are depicted in different schematics, itwill be appreciated that the orange movement can have a translationaland/or rotational component.

FIGS. 24A-24C schematically depict an example overall movementcomprising a combination of blue and orange movements. FIG. 24A depictsa patient's teeth in an original arrangement 2402 in which each of theteeth 2400 is located at an original position. In some embodiments, theoriginal positions of the teeth 2400 can correspond to positions of thepatient's teeth 2400 prior to any orthodontic treatment, after previousorthodontic treatment but prior to additional orthodontic treatment,during orthodontic treatment, etc. In the original arrangement 2402, theteeth 2400 may be poorly aligned such that there is excessive spacingbetween the teeth 2400, crowding of the teeth 2400, excessive rotationof one or more of the teeth 2400, and/or other alignment issues.

In some cases, the alignment of the teeth 2400 can be improved by movingthe teeth 2400 from their original positions to positions in which theteeth are better aligned (whether an ITA or an FTA) via a firstorthodontic intervention. The first orthodontic intervention can be, forexample, installation of any of the orthodontic appliances disclosedherein, such as orthodontic appliance 100. The first orthodonticintervention can move the teeth 2400 from their original positions tointermediate positions in an intermediate arrangement 2404 (as shown inFIG. 24B). The intermediate positions of the teeth 2400 can correspondto positions of the teeth 2400 after partial or complete orthodontictreatment. In some embodiments, the first movement comprises bluemovements (e.g., movement of the teeth in one dental arch relative toone another). Movement of the teeth 2400 from the original arrangement2402 to the intermediate arrangement 2404 can address one or morealignment issues within the dental arch. However, blue movement of theteeth 2400 from the original arrangement 2402 to the intermediatearrangement 2404 may not substantially modify a patient's occlusion(e.g., the relationship between the upper and lower dental arches).

To improve a patient's occlusion and move the patient's teeth into afinal arrangement 2406 (if not already achieved by the blue movements),a second orthodontic intervention can be employed to achieve a secondmovement of the teeth. For example, in some embodiments, the secondorthodontic intervention comprises an orthodontic elastic, a TAD, aplatform, surgery, or other intervention configured to move all of theteeth in a patient's arch relative to all of the teeth in the patient'sother arch. FIG. 24C shows the teeth 2400 in an original arrangement2402, after a first movement in the intermediate arrangement 2404, andafter a second movement in a final arrangement 2406. The second movementcan be a common movement shared by all of the teeth that moves the teethfrom the original arrangement 2402 and/or the intermediate arrangement2404 into the final arrangement 2406. In the example shown in FIG. 24C,the second movement comprises an anterior shift of all of the teeth inthe intermediate arrangement 2404 into the final arrangement 2406.

In some embodiments, the second orthodontic intervention can be the sametype of intervention as the first orthodontic intervention. For example,the first and second orthodontic interventions can comprise installationof an orthodontic appliance of the present technology. Moreover, thesecond movement can be the same type of movement (e.g., individual toothmovement, common movement, etc.) as the first movement, or the secondmovement can be a different type of movement from the first movement.

FIG. 25A illustrates teeth of a patient who has a class II malocclusionand FIGS. 25B and 25C illustrate two distinct approaches to improvingthe patient's occlusion in accordance with the present technology. InFIGS. 25B and 25C, the original positions of a patient's dental archesare depicted in a dashed line and the final positions of the arches aredepicted in a solid line. As shown in FIG. 25A, an upper dental arch2500 a is positioned more anteriorly than the lower dental arch 2500 bsuch that the patient has an overjet. During orthodontic treatment, theupper dental arch 2500 a and/or the lower dental arch 2500 b can bemoved to improve the patient's occlusion. In the approach depicted inFIG. 25B, all of the teeth of the patient's upper arch 2500 a are movedposteriorly according to the same transformation (e.g., via a commonmovement), and all of the teeth of the patient's lower arch 2500 b aremoved anteriorly according to the same movement (e.g., via a commonmovement). In these and other embodiments, the upper and lower arches2500 a, 2500 b can be moved the same distance. In embodiments in whichthe upper and lower arches 2500 a, 2500 b are moved similar distancesand toward one another, elastics can be used to accomplish the movementsof the arches.

Additionally or alternatively, the upper and lower arches 2500 a, 2500 bcould be moved by different distances. For example, the upper arch 2500a can be moved by a greater distance than the lower arch 2500 b, or viceversa. FIG. 25C depicts a method of improving the patient's occlusion bymoving all of the teeth of the patient's lower arch 2500 b anteriorly(e.g., via a common movement) without moving the upper arch 2500 a ofthe patient.

The movements of the upper and lower arches 2500 a, 2500 b relative toone another can be based, at least in part, on desired movements of thearches specified in the clinical instructions. For example, if thepatient is older and their facial tissues are less elastic, it may bepreferable to limit motion of the patient's upper arch 2500 a to preventor limit lip drooping as a result of loss of lip support that can occurwith movement of the patient's upper arch 2500 a. Movement of apatient's upper and lower arches 2500 a, 2500 b by different distancesmay not be achievable with an appliance and/or elastics, and may requireTADs and/or surgery.

5. Determining Whether to Perform Arch Registration

In some cases it may be beneficial to identify, evaluate, and/or modifythe planned common movements of all of the teeth in both of thepatient's dental arches (e.g., the purple movements) to facilitategeneration of an orthodontic treatment plan that is realistic,achievable, fast, and/or will lead to a more comfortable patientexperience. Several aspects of the present technology compriseidentifying the purple movements and evaluating whether the purplemovements are feasible based on the available orthodontic interventions,as certain movements of both dental arches may only be achievable withcertain orthodontic interventions. For example, moving both dentalarches in the same direction or moving the dental arches apart from oneanother are generally not feasible with an appliance or elastics, andinstead requires the use of TADs or surgical intervention.Identification of purple movements as part of the overall movement datacan thus better inform the treatment plan. The present technology alsocomprises evaluating a position of the dental arches in the first FTArelative to the OTA to determine if an error has been made when creatingthe first FTA. As noted above, in some embodiments, a human operator cancreate the first FTA by manipulating the teeth from the OTA until thealignment of the teeth is improved. It is possible that one or more ofthe dental arches may be unintentionally shifted while generating thefirst FTA, which may change the facial structure of the patient,increase the treatment time, and/or be otherwise undesirable orunattainable. Thus, it can be advantageous to identify, evaluate, and/ormodify the positions of the dental arches in the first FTA relative tothe positions of the dental arches in the OTA.

If the final positions and/or the movements of the arches areunfeasible, excessive, or otherwise undesirable, the process 2000 candetermine that an arch registration should be performed (process portion2010). Performing the arch registration can include modifying thepositions of the arches in the first FTA relative to the positions ofthe arches in the OTA. However, it is not always necessary to modify thepositions of the arches in the first FTA. For example, if the positionsof the arches in the first FTA are intentional and/or desirable, thepositions of the arches in the first FTA should not be modified. In suchcases, the process 2000 can include evaluating whether the purplemovements of the arches from the OTA to the first FTA can beaccomplished with the suggested, desired, available, or requiredinterventions. If the movements are achievable, the process 2000 candetermine that an arch registration does not need to be performed(process portion 2010). However, if the purple movements are notachievable with the orthodontic interventions that can be used duringtreatment, the process 2000 can provide such feedback to an operatorand/or suitable software. The operator and/or software can determine ifanother orthodontic intervention can be used to accomplish the purplemovements. If another orthodontic intervention cannot be used, theprocess 2000 can indicate that an arch registration should be performedto modify the positions of the arches and the purple movements. Thedecision regarding whether to perform an arch registration can be madeautomatically or manually.

In some embodiments it may be preferable to only move one of thepatient's dental arches during the orthodontic treatment. For example, apatient's upper dental arch can remain in substantially the sameposition from OTA to FTA, while the patient's lower dental arch is movedanteriorly. Such relative movement (or lack thereof) of the arches maybe desirable if the patient is older and their facial tissues are lesselastic, for example. In such cases, moving the upper arch posteriorlyto improve the patient's occlusion may result in undesirable loss of lipsupport and lip drooping. Thus, it may be advantageous to move only thebottom arch to improve the patient's occlusion. However, as previouslynoted, movement of only one dental arch, movement of both dental archesaccording to the same transformation, or movement of both dental archesin opposite directions may require specific orthodontic interventions.

6. Performing an Arch Registration

As previously noted, it may be beneficial to modify a position of one ormore of the patient's dental arches after the first FTA data and/or theoverall movement data have been obtained. For example, the dental archesmay be unintentionally shifted during generation of the first FTA data,which may be undesirable. As another example, simultaneous intrusion ofthe patient's upper arch and extrusion of the patient's lower arch maybe unfeasible with appliances alone and may require additionalorthodontic interventions (e.g., TADs, surgery). Thus, if the archeswere shifted unintentionally and there is no functional or aestheticreason for shifting the arches in such a manner, it may be preferable tomodify the first FTA data to eliminate and/or reduce such movement ofthe arches.

FIG. 26 is a flow diagram of an example process 2600 for performing anarch registration, and FIG. 27 is an example process 2700 for performingan arch registration algorithm. However, before the extended discussionof the processes embodied by FIGS. 26 and 27, the schematic diagramsshown in FIGS. 28A-29C will be described. FIGS. 28A-29C are intended asvisual aids to facilitate the discussion of processes 2600 and 2700.FIGS. 28A-29C show upper and lower dental arches (collectively “arches”)in different arrangements to illustrate various stages of the processes2800 and 2900. For ease of explanation, the movements of the archesdepicted in FIGS. 28A-29C are limited to translational displacements,and only in one dimension (along an anterior-posterior direction).However, as discussed herein, processes 2800 and 2900 can be performedfor arch movements involving displacements having one, two, or threetranslational components and/or one, two, or three rotationalcomponents. Although each of the arches is represented as a single boxin FIGS. 28A-29C, the arches can comprise multiple teeth. Because FIGS.28A-29C depict common movements in which of all of the teeth in both ofthe arches are moved (e.g., purple movements) and all of the teeth inone of the arches are moved (e.g., orange movements), the individualteeth of the arches are not depicted in FIGS. 28A-29C.

Turning now to FIG. 26, the process 2600 can comprise obtaining inputdata (process portion 2602), which can include OTA data, first FTA data,and/or overall movement data. Optionally, the input data can includeclinical instructions, as described herein. As an example, FIGS. 28A-28Ceach show the upper and lower dental arches in original positions(schematically depicted as white boxes with dashed edges and labeled“OTA”) characterized by the OTA data. FIGS. 28A-28C also each show thearches in preliminary final positions (schematically depicted as boxeswith diagonal lines and dashed edges and labeled “FTA1”) characterizedby the first FTA data. FIG. 28A includes arrows depicting the movementsof the arches characterized by the overall movement data (e.g.,movements of the arches from their original positions to theirpreliminary final positions). In some embodiments, a movement of adental arch can comprise an orange movement (e.g., a movement of all ofthe teeth in the dental arch according to the same transformation).

Referring to FIG. 27, the process 2700 of performing the archregistration algorithm can include registering (e.g., aligning) thefirst FTA data to the OTA data (process portion 2702). In someembodiments, for example as shown in FIG. 28B, registering the first FTAdata to the OTA data can comprise obtaining second FTA datacharacterizing modified final positions of the arches (schematicallydepicted as boxes with diagonal lines and solid edges and labeled“FTA2”). The second FTA data can be obtained by modifying the first FTAdata according to purple movement data characterizing a purple movement(depicted as arrows in FIG. 28B). As previously noted, a purple movementcan comprise a common movement of all of the teeth in both of thearches. The purple movement can comprise a transformation that isapplied to all of the teeth in both of the arches, and in someembodiments, the transformation is rigid. Reducing a distance betweenthe final positions and the original positions of the arches can bebeneficial for one or more reasons including, but not limited to,improving feasibility of the treatment, reducing treatment time,increasing patient comfort, reducing the number and invasiveness ofadditional orthodontic interventions, maintaining the patient's facialstructure, etc.

As shown in FIG. 28A, a patient's occlusion (e.g., the positionalrelationship between the upper and lower arch) when the arches are atthe preliminary final positions may be different than the patient'socclusion when the arches are at the original positions. If the secondFTA data is obtained by rigidly transforming the first FTA data, theremay be one or more residual distances (depicted as arrows in FIG. 28C)between the modified final positions and the original positions of thearches. Such residuals can correspond to orange movements of the dentalarches (e.g., movements of all of the teeth in one of the patient'sdental arches according to a common movement). Thus, the process 2700can include obtaining orange movement data characterizing orangemovements of the patient's dental arches (process portion 2704). Theorange movements can be based on the overall movements and the purplemovements. For example, the orange movement of each arch can be equal tothe overall movement of the arch minus the purple movement of the arch.

In various embodiments, the purple movement data, the orange movementdata, and/or the second FTA data may comprise symbolic data. Forexample, the orange movement data can be equivalent to the overallmovement data minus the purple movement data and/or the second FTA datacan be equivalent to the first FTA data minus the purple movement data.If the overall movement data is numeric but the purple movement data issymbolic, the orange movement data and the second FTA data will also besymbolic.

Thus, the process 2700 can include solving for the unknown symbolicvariables (process portion 2706). To solve for the unknown symbolicvariables, an analysis such as a regression analysis, a matrixdecomposition analysis, or another suitable analysis can be performed.The analysis can be linear or nonlinear. For example, the matrixdecomposition analysis can comprise a singular value decomposition, LUdecomposition, rank factorization, Cholesky decomposition, QRdecomposition, RRQR factorization, interpolative decomposition,eigendecomposition, Jordan decomposition, Schur decomposition, QZdecomposition, Takagi's factorization, scale-invariant decomposition,polar decomposition, Mostow's decomposition, Sinkhorn normal form,sectoral decomposition, Williamson's normal form, combinations thereof,or any other suitable matrix decomposition or factorization. Theregression analysis can include an ordinary least squares regression, anonlinear least squares regression, a weighted least squares regression,a robust regression, combinations thereof, or any other suitableregression method. Solving for the symbolic variables can includefinding the numeric values of the symbolic variables that minimize theorange movements (e.g., the distances between the original and modifiedfinal positions of each arch). The numeric values for the symbolicvariables can then be entered into the purple movement data, the orangemovement data, and the second FTA data, which can be obtained as outputsof processes 2000 and 2600.

As previously noted, the process of registering the first FTA data tothe OTA data to obtain the second FTA data can comprise determining thepurple and/or orange movements that minimize the distances between themodified final positions of the arches and the original positions of thearches while maintaining a desired occlusion between the arches. Theregistration can be subject to one or more constraints and/or weightingsthat influence the manner in which the distances between the modifiedfinal and original positions of the arches are minimized, and therebythe modified final positions of the arches. The constraints and/orweightings can be based, at least in part, on the clinical instructions,biological factors (e.g., relative speeds of certain types of movements,age of the patient, etc.), and/or other relevant information. Forexample, as discussed with reference to FIGS. 25A-25C, in some cases itmay be preferable to equally minimize movement of both arches, whereasin other cases it may be preferable to minimize movement of one arch.

FIGS. 28A-28C depict an example in which the magnitudes of the orangemovements of the upper and lower arches are substantially equivalent,but the directions of the orange movements of the upper and lower archesare opposite. In this example, as the arches are moved from theiroriginal positions to their modified final positions according to theorange movements, the arches will move equal distances towards oneanother. Such movements of the arches can be accomplished with elastics,and so may be desirable for a patient who is not amenable to using TADsor receiving surgery.

However, as previously noted, in some cases it may be desirable to movethe arches by different amounts. For example, in some cases it may bedesirable to move only one of the patient's arches (see FIG. 25C). FIGS.29A-29C depict an example of performing an arch registration such thatthe upper arch does not substantially move from its original position toits modified final position, while maintaining the occlusioncharacterized by the first FTA data. Such a registration could beperformed, for example, when the clinical instructions indicate that thelower arch alone should be moved with TADs and/or surgery. Similar toFIGS. 28A-28C, FIGS. 29A-29C schematically depict a patient's dentalarches in original positions, preliminary final positions, and modifiedfinal positions. As previously described, the purple movement (andthereby the orange movements and the second FTA data) can initially besymbolic. An analysis such as the analyses described above can beperformed to determine the numerical values of the symbolic variablessuch that the orange movements are minimized. However, in the embodimentdepicted in FIGS. 29A-29C, the upper arch can be weighted in theminimization analysis to a much greater extent than the lower arch. As aresult, the analysis will obtain numerical values of the symbolicvariables that reduce the magnitude of the orange movement of the upperarch to a greater extent than the magnitude of the orange movement ofthe lower arch. In some embodiments, the upper arch and lower arch canbe weighted such that the analysis obtains an orange movement of theupper arch with a negligible magnitude (e.g., the modified finalposition of the upper arch is substantially equivalent to the originalposition). In such embodiments, a magnitude of the orange movement ofthe lower arch can correspond to a magnitude of the purple movement,which can correspond to a distance between the preliminary finalposition and the original position of the upper arch.

In the previously described embodiment, the arch registration algorithmfor minimizing the movement of one arch can be substantially similar tothe arch registration algorithm for minimizing the movements of botharches, except for the weighting of the arches in the minimizationanalysis. However, in some embodiments a different arch registrationalgorithm for minimizing the movement of one arch can be employed. Suchalgorithm can comprise determining a purple movement (depicted as arrowsin FIG. 29B) having a magnitude substantially equivalent to a distancebetween the original position and the preliminary final position of theupper arch such that the modified final position of the upper arch issubstantially equivalent to the original position of the upper arch.Accordingly, the residual distances (depicted as arrows in FIG. 29C)characterizing the orange movements of the arches can have differentmagnitudes. A magnitude of the orange movement of the upper arch can benegligible whereas a magnitude of the orange movement of the lower archcan be substantially equivalent to a magnitude of the purple movement.

7. Performing a Tooth Registration

Referring back to FIG. 20, the process 2000 can include performing atooth registration (process portion 2016). As shown in FIG. 20, thetooth registration can occur either directly after the process 2000determines that an arch registration should not be performed or afterthe process 2000 performs an arch registration. A tooth registration candiffer from an arch registration in that the tooth registration can beperformed to obtain movements of the teeth in a single dental archrelative to one another (e.g., blue movement) and movements of all ofthe teeth in a single dental arch according to a common movement (e.g.,orange movements). FIG. 30 is a flow diagram of an example process 3000for performing a tooth registration and FIG. 31 is a flow diagram of anexample process 3100 for performing a tooth registration algorithm.FIGS. 32A-32E are schematic diagrams provided as visual aids tofacilitate the discussion of processes 3000 and 3100. In particular,FIGS. 32A-32E show first, second, third, and fourth teeth 3200 a, 3200b, 3200 c, and 3200 d (collectively “teeth 3200”) in differentarrangements to illustrate various stages of the processes 3000 and3100. For ease of explanation, the movements of the teeth 3200 depictedin FIGS. 32A-32E are limited to translational displacements, and only intwo dimensions (x and y). However, as discussed herein, processes 3000and 3100 can be performed for displacements having one, two, or threetranslational components and/or one, two, or three rotationalcomponents. Moreover, although four teeth 3200 a-d are shown in FIGS.32A-32E, one or both of the processes 3000 and 3100 can be performed forfewer than four teeth (e.g., one tooth, two teeth, three teeth) or morethan four teeth (e.g., five teeth, six teeth, seven teeth, eight teeth,nine teeth, 14 teeth, 28 teeth, 32 teeth, etc.). In some embodiments,one or both of the processes 3000 and 3100 are performed for all of theteeth in one or both of the patient's jaws.

With reference to FIG. 30, the process 3000 includes obtaining inputdata 3002. The input data 3002 can include OTA data characterizingoriginal positions of the teeth and either first FTA data if an archregistration has not been performed or second FTA data if an archregistration has been performed. The input data 3002 can also includemovement data characterizing an overall movement of each tooth from itsoriginal position to its final position and/or clinical instructions. Asan example, FIG. 32A shows first-fourth teeth 3200 in an originalarrangement 3202 (schematically depicted as white boxes with dashededges) and in a final arrangement 3204 (schematically depicted as boxeswith diagonal lines and dashed edges), with arrows representing theoverall movements 3210 a-d of the teeth 3200 from the originalarrangement 3202 to the final arrangement 3204. The overall movementdata can comprise one or more displacements of each tooth defined fromone or more locations on the teeth in the original arrangement to thecorresponding locations on the teeth in the final arrangement. FIG. 32A,for example, shows the displacements 3210 a-d defined from a singlelocation 3208 a-d on each of the first-fourth teeth 3200 a-d in theoriginal arrangement 3202 to the corresponding locations 3208 a-d on thefirst-fourth teeth 3200 a-d in the final arrangement 3204. In someembodiments a single location on each tooth can be used to define amovement of the tooth (as in FIGS. 32A-32E), and in some embodimentsmultiple locations on each tooth can be used to define the movement(see, for example, FIG. 21).

The process 3000 can continue with performing a tooth registrationalgorithm (process portion 3004) with the input data obtained at processportion 3102 to determine output data (process portion 3006). The outputdata can include, for example, orange movement data characterizingorange movements of the teeth in which all of the teeth in the dentalarch (e.g., first-fourth teeth 3200 a-d) are moved according to a commonmovement. As previously noted, the common movement can comprise atransformation that is applied to all of the teeth in the arch.Additionally or alternatively, the output data can include blue movementdata characterizing blue movements of the teeth. As previously noted, ablue movement can comprise a movement of one of the teeth in thepatient's dental arch relative to other teeth in the same dental arch.In some embodiments, the blue movement is unique and/or individual tothe tooth to which it is applied. The output data can also comprise ITAdata characterizing intermediate positions of the teeth in the dentalarch after the teeth have been moved according to the blue movements. Asdiscussed herein, such output data can be useful for selecting aparticular orthodontic intervention to accomplish the movements, fordetermining one or more design features of an orthodontic appliance foruse during the treatment, etc. As but one example, if the treatment planincludes orange movements, it may be advantageous to position hooks of aheat treatment fixture for setting a shape of an appliance at theintermediate positions (instead of the final positions), as theappliance might only accomplish the blue movements.

FIG. 31 is a flow diagram showing an example tooth registrationalgorithm 3104 configured to decompose input movements intosub-components, thereby identifying the contribution of different forcesto the resulting overall movement. As depicted at process portion 3102,performing the decomposition algorithm can include registering the FTAdata to the OTA data to obtain the ITA data. Registering the FTA data tothe OTA data can comprise applying a transformation to the FTA data. Thetransformation 3212, for example, can be a rigid transformation. Thetransformation 3212 can be applied to a single location on each of theteeth or the transformation 3212 can be applied to multiple locations oneach of the teeth. As an example, FIG. 32B shows first-fourth teeth 3200a-d in the final arrangement 3204 and an intermediate arrangement 3206(schematically depicted as boxes with diagonal lines and solid edges).In FIG. 32B, the transformation 3212 has been applied to a singlelocation 3208 a-d on each of the teeth 3200 a-d.

According to several aspects of the technology, the transformation 3212substantially corresponds to an orange movement in which all of theteeth in one of the patient's dental arches are moved according to thesame translations and rotations. In the example depicted in FIG. 32B,the first-fourth teeth 3200 a-d in the final arrangement 3204 have beentranslated in the same direction and with the same magnitude withrespect to the final arrangement 3204. In various embodiments, the rigidtransformation 3212 may be a symbolic transformation. For example, inFIG. 32B the teeth 3200 a-d may have been translated from the finalarrangement 3204 to the intermediate arrangement 3206 in a singledirection by a variable ‘y’ amount. As will be described in greaterdetail below, the algorithm can be configured to solve for the symbolicvariables in the transformation 3212.

Performing the tooth registration algorithm can further includeobtaining blue movement data (process portion 3104) characterizing bluemovements of the teeth between the intermediate arrangement and theoriginal arrangement. In some embodiments, obtaining the blue movementdata can comprise minimizing the distances between a position of eachtooth in the original arrangement 3202 and a position of the tooth inthe intermediate arrangement 3206. In some embodiments, obtaining theblue movement data comprises determining the displacements 3214 a-dbetween the selected locations 3208 a-d of each of the teeth 3200 a-d inthe intermediate arrangement and the original arrangement. Thedisplacements 3214 a-d, which correspond to blue movements of the teeth,can also be considered residuals or errors between the intermediatepositions of the teeth 3200 a-d and the original positions of the teeth3200 a-d. The displacements 3214 a-d can be found in terms of symbolicvariables. For example, consider a scenario in which the first tooth3200 a has an original position of (x1,y1) at location 3208 a and afinal position of (x2,y2) at location 3208 a in the second arrangement3204. In process portion 3102, a first tooth 3200 a can undergo a rigidtransformation 3212 such that the first tooth 3200 a is translated by −yamount along a first dimension. In such a scenario, the first tooth 3200a has an intermediate position of (x2,(y2−y)). In such embodiments, thevariable ‘y’ is symbolic, and the values ‘x2’ and ‘y2’ are known,numerical values that were obtained when obtaining the FTA datacharacterizing the final position of the first tooth 3200 a (e.g., bymoving the tooth from its original position according to clinicalinstructions). In some embodiments, ‘x2’ and ‘y2’ can be determined bytransforming the teeth from the original arrangement to the finalarrangement according to a known transformation.

To solve for the unknown symbolic variables (e.g., at process portion3106), an analysis such as a regression analysis, a matrix decompositionanalysis, or another suitable analysis can be performed. The analysiscan be linear or nonlinear. For example, the matrix decompositionanalysis can comprise a singular value decomposition, LU decomposition,rank factorization, Cholesky decomposition, QR decomposition, RRQRfactorization, interpolative decomposition, eigendecomposition, Jordandecomposition, Schur decomposition, QZ decomposition, Takagi'sfactorization, scale-invariant decomposition, polar decomposition,Mostow's decomposition, Sinkhorn normal form, sectoral decomposition,Williamson's normal form, combinations thereof, or any other suitablematrix decomposition or factorization. The regression analysis caninclude an ordinary least squares regression, a nonlinear least squaresregression, a weighted least squares regression, a robust regression,combinations thereof, or any other suitable regression method. Aspreviously noted, the algorithm can include solving for the symbolicvariables that minimize the distances (e.g., errors) between the teethin the original and intermediate arrangements 3202, 3206. In someembodiments, the distances between the teeth can be minimized equally.In some embodiments, and as discussed herein, minimizing the distancesbetween the teeth may be subject to one or more constraints and/or beweighted such that the distances between the teeth are not minimizedequally.

In some embodiments, an analysis including the method of least squaresor a similar method can be conducted in which the displacements 3214 a-dare squared and summed. The symbolic function can be minimized (e.g., bysetting a derivative of the function equal to zero), and the symbolicvariables solved for. The numeric values for the symbolic variables canthen be entered into ITA data to solve for numeric values of theintermediate positions. Additionally or alternatively, the numericvalues for the symbolic variables can be plugged into the orangemovement data and/or blue movement data to solve for the orange and/orblue movements. In some embodiments, the transformation 3212 correspondsto orange movements of the teeth 3200 a-d and/or the displacements 3214a-d correspond to blue movements of the teeth 3200 a-d. The orangemovements can have the same magnitude as transformation 3212 and/or theblue movements 3218 a-d can have the same magnitude as the displacements3214 a-d. In some embodiments, for example as shown in FIG. 32E, theorange movements have an opposite direction as transformation 3212and/or the blue movements have opposite directions as the correspondingdisplacements 3214 a-d.

When computing the displacement between an intermediate position and anoriginal position of a tooth, one or more locations on the tooth may beselected for evaluation. Use of fewer locations is associated with alower computational cost; however, using fewer locations may alsocompromise fidelity of the algorithm. For example, consider a tooth thatis to undergo rotation but no translation. Based, on the originalposition and the prescribed final position of the tooth, the movementdata may indicate that the tooth should be rotated 90 degrees from theoriginal position to the final position. If the tooth is only rotated 50degrees via the orange movements, the algorithm should compute anon-zero angular displacement between the intermediate position of thetooth and the original position of the tooth. However, if the locationthat is evaluated is positioned at the center of rotation of the tooth(see FIGS. 32A-32E), the algorithm will compute an angular displacementof zero between the intermediate and original positions. Accordingly, itmay be advantageous to evaluate the displacements between multiplelocations on each tooth.

In its simplest form, a least squares analysis solves for the symbolicvariables associated with the movements of the tooth by reducing thedisplacements between the original positions and the intermediatepositions for each tooth by an even amount, thereby simulating the teethmoving at the same rate. However, as noted above with respect to thearch registration, it may be advantageous to reduce the displacements byan uneven amount. Orthodontic tooth movement is a complex biologicalprocess, and certain teeth move at a slower rate than others. Moreover,certain types of tooth movements occur at a slower rate than others. Toimprove fidelity of the algorithm, weighting can be applied todisplacements corresponding to specific teeth and/or specific locationson the teeth to simulate various rates and extents of movement moreaccurately. A larger weight can be assigned to teeth and/or locationsthat move more slowly and/or are harder to move in reality. For example,bone formation occurs at a faster rate than bone resorption. Thus,locations on a tooth that are on a compression side of the tooth (i.e.,the side at which bone resorption is occurring) can be assigned a largerweight than locations on a tension side of the tooth (i.e., the side atwhich bone formation is occurring). In some embodiments, certain teethare weighted more heavily in the analysis by evaluating more points onthe teeth. For example, the number of points evaluated for each toothcan be proportional to the surface area of a root of the tooth tosimulate the slower movement of a tooth with a larger root (and viceversa) more accurately.

B. Obtaining an Orthodontic Treatment Plan

Referring back to FIG. 19, the orthodontic treatment process 1900 caninclude obtaining an orthodontic treatment plan (process portion 1904).As previously noted, orthodontic treatment can involve moving apatient's teeth according to specific movements such that the teeth aremoved to desired, final locations. The orthodontic treatment can includeone or more specific types of movements, such as a movement of all ofthe teeth in one of the patient's dental arches according to the sametransformation, a movement of one of the teeth in one of the patient'sdental arches, and/or others. Moreover, different types of toothmovements can be accomplished by different types of orthodonticinterventions. For example, a movement of all of the teeth in one of thepatient's dental arches can be accomplished by surgery, growth of thepatient, TADs, elastics, platforms, etc., whereas a movement of onlysome of the patient's teeth in one of the patient's dental arches can beaccomplished by an appliance such as the appliances disclosed herein.Thus in various embodiments, an orthodontic treatment plan can includeone or more suggested orthodontic interventions to accomplish one ormore types of tooth movements.

In some embodiments, the orthodontic treatment plan can include one ormore suggested parameters of the orthodontic interventions. For example,as detailed below, the orthodontic treatment plan can include a designof an orthodontic appliance, which may include a stiffness of one ormore portions of the appliance, a preset shape of one or more portionsof the appliance, and/or others. In some embodiments, the orthodontictreatment plan can suggest an attachment location for an elastic, alocation of a TAD in the patient's jaw, a type of surgery, etc.

In some embodiments, the orthodontic treatment plan includes suggestionswith regards to coordination of the component movement(s) and/or theorthodontic intervention(s). For example, the orthodontic treatment plancan indicate that a patient's teeth should be moved sequentially from afirst arrangement (e.g., the first arrangement 502) to a secondarrangement (e.g., the second arrangement 504) to a third arrangement(e.g., the third arrangement 506) or from the first arrangement to thethird arrangement to the second arrangement. In various embodiments, anorthodontic treatment plan can indicate that the teeth should be movedfrom the first arrangement to the second and third arrangements at leastpartially simultaneously. Still, in some embodiments an orthodontictreatment plan can be silent as to a suggested order of the componentmovements.

In some embodiments, obtaining the treatment plan can comprise modifyingthe treatment approach (e.g., by separating the movements into multiplestages, by modifying the selection of orthodontic intervention toaccomplish the movements, etc.). For example, if the movements includesimultaneously extruding a patient's lower dental arch and intruding theupper arch, TADs may be required to accomplish the movements.Accordingly, the method may include modifying the suggested orthodonticintervention to include TADs. As previously described, the process canrepeat until an acceptable and/or preferred treatment plan is obtained.

1. Obtaining a Design of an Orthodontic Intervention

In some embodiments, an orthodontic treatment plan can include datacharacterizing a design of an orthodontic intervention. For example, thetreatment plan can include data characterizing an appliance (e.g., ashape or a material property of an appliance, a digital model of anappliance, etc.). A 3D configuration of an appliance disclosed hereincan be based, at least in part, on a shape of a fixture to which theappliance is conformed during manufacturing of the appliance. Thus, insome embodiments a treatment plan includes a design of a heat treatmentfixture or other auxiliary device used to manufacture an appliance orother intervention.

In various embodiments, an orthodontic treatment can involve moving apatient's teeth according to multiple types of movements (e.g., bluemovements, orange movements, purple movements, etc.). In someembodiments, each type of movement can be accomplished by oneorthodontic intervention. For example, appliances of the presenttechnology may be configured to move teeth in one of a patient's dentalarches relative to other teeth in the same dental arch (e.g., accordingto blue movements), but are not configured to accomplish commonmovements of all of the patient's teeth in one or both arches (e.g.,orange movements to be accomplished by elastics, purple movements to beaccomplished by surgery, etc.). In these and other embodiments, it maybe advantageous to locate the attachment portions of the appliance atpositions substantially corresponding to positions of the teeth afterthey have been moved from their original positions according to the bluemovements (e.g., at intermediate positions rather than final positions).Positioning the attachment portions at intermediate positions (e.g., atpositions after the teeth have been moved from OTA according to bluemovements) instead of final positions can prevent or limit impingementof the patient's gingiva by the appliance when the appliance isinstalled. In some embodiments, the positions of the attachment portionscan be based, at least in part, on the blue movements of the teeth, theorange movements of the teeth, and/or the purple movements of the teeth.For example, if an orthodontic treatment plan includes moving each of apatient's dental arches with an appliance secured to one or more TADs ineach of the patient's jaws, the appliance can be configured toaccomplish blue movements, orange movements, and/or purple movements.Accordingly, the positions of the securing portions can be based on thedesired positions of the teeth after some or all of the blue, orange,and/or purple movements have been accomplished.

Appliances of the present technology can be configured to impart forceson a patient's teeth to move the teeth from original positions todesired, final positions. In some embodiments, an appliance isconfigured to apply a specific force to one or more teeth based on a 3Dconfiguration of the appliance. For example, an appliance can haveattachment portions located at positions based on desired positions ofthe patient's teeth. The 3D configuration can be formed by manipulatingthe appliance from a planar configuration into the 3D configuration(e.g., by securing the appliance to a fixture) and setting a shape ofthe appliance (e.g., via heat treatment, cold working, plasticdeformation, etc.). When the appliance is in the 3D configuration, anattachment portion of the appliance is located at an intended positionwith respect to other attachment portions of the appliance and/or ananchor of the appliance. The intended position of the attachment portioncan correspond to or be derived from a desired position of the tooth towhich the attachment portion is configured to be secured. In operation,the appliance can move the tooth toward its desired position by movingthe attachment portion toward its intended position.

Accurately locating attachment portions of an appliance at theirintended positions while forming a 3D configuration of the appliance isessential to the efficacy of moving a patient's teeth to their desired,final positions. If an attachment portion is located at an incorrectposition when the appliance is in the 3D configuration, the tooth maynot reach its desired position when the attachment portion returns toits pre-set position. Such errors in locating the attachment portions intheir intended positions can result in a need for additional appliancesto complete the treatment, increased cost and time of treatment, and/orpatient dissatisfaction with the treatment.

Errors in forming the 3D configuration of the appliance can occur whilemanipulating the appliance from the planar configuration into the 3Dconfiguration, including while securing the appliance to the fixtureand/or setting a shape of the appliance. For example, when securing theappliance to the fixture, the attachment portion can be secured at aposition deviating from the intended position if there is excessive playbetween the attachment portion and a securing portion of the fixtureconfigured to retain the attachment portion. In some cases, a securingportion of a fixture must be designed to accommodate attachment portionsof a range of sizes due to manufacturing tolerances and errors, whichcan result in play between certain attachment portions and the securingportion.

Various embodiments of the present technology comprise methods ofmanufacturing an orthodontic appliance with high accuracy and precision.In some embodiments, the present technology comprises a fixtureconfigured to releasably retain the appliance in the 3D configurationsuch that attachment portions of the appliance are located in intendedpositions corresponding to or derived from desired positions of theteeth to be treated. The fixture can comprise a body portion and one ormore securing portions. In some embodiments, each of the securingportions is configured to retain a corresponding attachment portion ofthe appliance at an intended position.

FIG. 33A depicts a fixture 3300 configured in accordance with severalembodiments of the present technology. The fixture 3300 can be similarto fixture 1700, except as described below. The fixture 3300 cancomprise a body portion 3302 and one or more securing portions 3304carried by the body portion 3302. The body portion 3302 and the securingportions 3304 can be monolithic or the securing portions 3304 can beseparate pieces that are coupled to the body portion 3302. In someembodiments, the fixture 3300 includes one or more structural componentsthat generally do not directly engage the appliance and rather stabilizethe body portion and/or securing portions. The fixture in FIG. 33A, forexample, includes a stabilizer 3306 that extends between opposite sidesof the body portion 3302.

The fixture 3300 is configured to be releasably secured to an applianceand retain the appliance in a desired 3D configuration. In someembodiments, the appliance is releasably secured to the fixture 3300such that an anchor of the appliance substantially conforms to the bodyportion 3302 of the fixture 3300. Additionally or alternatively,attachment portions of the appliance may be releasably secured to thesecuring portions 3304 of the fixture 3300.

As shown in FIG. 33A, the body portion 3302 of the fixture 3300 can havea first surface 3303 at a lingual side of the fixture 3300 and a secondsurface (not visible) at the buccal side of the fixture 3300 andopposite the first surface 3303 along a thickness of the body portion3302. The first surface 3303 and/or the second surface can have a shapesubstantially corresponding to a shape of the patient's gingiva in theOTA, the FTA, and/or one or more ITAs. In some embodiments, the bodyportion 3302 can be a modified version of the gingiva portion of the OTAdigital model, the FTA digital model, and/or another suitable digitalmodel. For example, the body portion 3302 can be enlarged or thickenedwith respect to the gingiva portion of the OTA digital model and/or theFTA digital model to prevent or limit impingement of the patient'sgingiva by the appliance once installed. In some embodiments, theappliance is releasably secured to the fixture 3300 such that one ormore portions (e.g., an anchor, an arm, etc.) of the appliancesubstantially conform to the first surface 3303.

The securing portions 3304 of the fixture 3300 can be configured toreleasably secure the appliance to the fixture 3300 such that theappliance is manipulated into the desired 3D configuration. For example,each of the securing portions 3304 can be configured to releasablyretain an attachment portion of the appliance at an intended positionwith respect to the anchor, other attachment portions, etc. Accordingly,the appliance can be shape set (e.g., heat treated, etc.) while securedto the fixture 3300 such that the attachment portion remains located atthe intended position once the appliance is removed from the fixture3300. The intended position at which the securing portion 3304 isconfigured to retain the attachment portion can substantially correspondto and/or be derived from a desired position of the tooth to be treated.In operation, the arm can move the attachment portion to the intendedposition, thereby moving the tooth to the desired position via theattachment portion.

FIGS. 33B and 33C are front and side views, respectively, of one of thesecuring portions 3304 shown isolated from the fixture 3300. FIG. 33D isa front view of the securing portion 3304 shown in FIGS. 33A-33Creleasably secured to an attachment portion 3340 of an appliance. Asshown in FIGS. 33B and 33C, the securing portion 3304 can comprise asurface 3305 configured to be positioned adjacent to and/or in contactwith an attachment portion 3340. The securing portion 3304 can includeone or more protrusions 3308 configured to locate the attachment portion3340 of the appliance at the intended position. For example, thesecuring portion 3304 depicted in FIGS. 33A-33D includes a firstprotrusion 3308 a, a second protrusion 3308 b, and a third protrusion3308 c (collectively referred to as “protrusions 3308”) extending awayfrom the surface 3305. The protrusions 3308 define channels therebetweenthat receive the attachment portion 3340. The channels can comprise afirst channel 3310 a and a second channel 3310 b (referred tocollectively as “channels 3310”). The securing portion 3304 can furtherinclude first and second grooves 3312 a and 3312 b (referred tocollectively as “grooves 3312”) configured to receive a fastener atleast partially therein. As shown in FIG. 33D, the attachment portion3340 can be positioned against the surface 3305 between the protrusions3308.

Although the channels 3310 in FIGS. 33A-33D are defined by protrusions3308 extending away from the surface 3305, in some embodiments thesecuring portion 3304 includes channels 3310 formed by recesses in thesurface 3305. The channels 3310 would thus extend into the thickness ofthe securing portion 3304. In these and other embodiments, the securingportion 3304 may not include protrusions 3308 or channels 3310. Instead,the securing portion 3304 can comprise printed markings, for example, onthe securing portion 3304 that are configured to indicate the intendedposition of the attachment portion 3340.

As described in greater detail below, the securing portion 3304 caninclude one or more recesses 3312 and/or openings 3314 configured toreceive ligature wire or another fastener at least partially therein. Invarious embodiments, the securing portion 3304 comprises one or morestructural components (see structural component 3316 in FIG. 33C)configured to increase rigidity of the securing portion 3304.

According to some embodiments, for example as shown in FIG. 33D, theattachment portion 3340 can be positioned in, at, or adjacent to thesecuring portion 3304 such that the attachment portion 3340 is locatedat its intended position. In some embodiments, the attachment portion3340 is positioned substantially parallel with and/or in contact withthe surface 3305 of the securing portion 3304. In some embodiments, thesecuring portion 3304 and/or protrusions 3308 include one or moreengagement surfaces 3318 configured to facilitate alignment of theattachment portion 3340 with the intended position. For example, thesecuring portion 3304 shown in FIGS. 33A-33D includes a first engagementsurface 3318 a, a second engagement surface 3318 b, and a thirdengagement surface 3318 c. The first engagement surface 3318 a can be asurface of the first protrusion 3308 a, the second engagement surface3318 b can be a surface of the second protrusion 3308 b, and the thirdengagement surface 3318 c can be a surface of third protrusion 3308 c.

As shown in FIG. 33D, in some embodiments the attachment portion 3340 ofthe appliance is generally T-shaped. The attachment portion 3340 cancomprise a first projection 3342 extending along a first direction D1, asecond projection 3344 extending along the first direction D1, a thirdprojection 3346 extending along a second direction D2, and/or a fourthprojection 3348 extending along the second direction D2 (collectively“projections 3342-3348” and “directions D”). In some embodiments, forexample as shown in FIG. 33D, the first direction D1 is generallyorthogonal to the second direction D2. Although FIG. 33D depicts theattachment portion 3340 with four projections 3342-3348, other numbersof projections are possible. Moreover, the projections 3342-3348 mayextend along different directions D than the two generally orthogonaldirections D1, D2 depicted in FIG. 33D. For example, each of theprojections 3342-3348 can extend along a unique direction.

To locate the attachment portion 3340 at the intended position, theattachment portion 3340 can be positioned in, at, or adjacent to thesecuring portion 3304 of the fixture 3300 such that the attachmentportion 3340 engages the engagement surfaces 3318. For example, as shownin FIG. 33D, the first projection 3342 of the attachment portion 3340can engage the first engagement surface 3318 a, the second projection3344 can engage the second engagement surface 3318 b, and the thirdprojection 3346 can engage the third engagement surface 3318 c. In someembodiments, a first vertical surface 3342 a of the first projection3342 can be configured to contact the first engagement surface 3318 a, afirst vertical surface 3344 a of the second projection 3344 can beconfigured to contact the second engagement surface 3318 b, and a firsthorizontal surface 3346 a of the third projection 3346 can be configuredto contact the third engagement surface 3318 c. Accordingly, a secondvertical surface of the first projection 3342, a second vertical surfaceof the second projection 3344, a second horizontal surface of the thirdprojection 3346, and all surfaces of the fourth projection 3348 are notconstrained by the securing portion 3304. This design of the securingportion 3304 allows the attachment portion 3340 to be constrained in twodegrees of freedom, e.g., along the first and second directions D1, D2.Moreover, in some cases a distance between the first and second verticalsurfaces of the first projection 3342, the first and second verticalsurfaces of the second projection 3344, the first and second horizontalsurfaces of the third projection 3346, etc. may be different than anintended distance between the respective surfaces due to tolerancestacking and/or manufacturing errors. The securing portions disclosedherein address these limitations by allowing attachment portions ofvarious widths to be aligned at the intended position.

Although FIGS. 33A-33D depict a securing portion 3304 including threeengagement surfaces 3318, other configurations are possible. Thesecuring portion 3304 can include two or more engagement surfaces 3318configured to engage two or more surfaces of the attachment portion3340. In various embodiments, the securing portion 3304 includes threeor more engagement surfaces 3318 configured to engage three or moresurfaces of the attachment portion 3340. In various embodiments, forexample, a securing portion can include a first protrusion including (i)a first engagement surface configured to engage the second verticalsurface of the first projection of the attachment portion and (ii) asecond engagement surface configured to engage the first horizontalsurface of the third projection of the attachment portion and a secondprotrusion including a third engagement surface configured to engage thefirst vertical surface or the second vertical surface of the secondprojection. In some embodiments, the securing portion includes a firstengagement surface configured engage the first horizontal surface of thethird projection, a second engagement surface configured to engage thefirst horizontal surface of the fourth projection, and the first orsecond vertical surface of the first or second projections.

The first engagement surface 3318 a, the second engagement surface 3318b, and/or the third engagement surface 3318 c can have a shapecorresponding to and/or derived from a shape of a correspondingprojection (e.g., the first projection 3342, the second projection 3344,the third projection 3346, etc.). For example, as shown in FIG. 33D,each of the first, second, and third engagement surfaces 3318 a, 3318 b,3318 c can be substantially flat to engage a substantially flat surfaceof the first, second, and third projections 3342, 3344, 3346 of theattachment portion 3340, respectively. As shown in FIGS. 33B-33D, thefirst and second engagement surfaces 3318 a, 3318 b can be substantiallyparallel to each other and/or the third engagement surface 3318 c can besubstantially orthogonal to the first engagement surface 3318 a and/orthe second engagement surface 3318 b. In some embodiments, the firstengagement surface 3318 a is spaced apart from the second engagementsurface 3318 b and/or the third engagement surface 3318 c along thesecond direction D2. The first engagement surface 3318 a and/or thethird engagement surface 3318 c can be spaced apart from the secondengagement surface 3318 b along the first direction D1.

Prior to setting a shape of the appliance, the appliance can bereleasably secured to the fixture 3300. In various embodiments, theattachment portion 3340 is releasably secured to the securing portion3304 of the fixture 3300. For example, as shown in FIG. 33D, one or moreelongated members 3350 (e.g., a ligature wire, a cord, a braid, a coil,etc.) can be wrapped around the attachment portion 3340 and the securingportion 3304. A first elongated member 3350 a can be wrapped around theattachment portion 3340 and the securing portion 3304 such that thefirst elongated member 3350 a is positioned within a first recess 3312 ain the securing portion 3304 and extends across the attachment portion3340 along a diagonal path between a first corner between the first andfourth projections 3342, 3348 and a second corner between the second andthird projections 3344, 3346. Such a diagonal path can reduce oreliminate play between the attachment portion 3340 and the securingportion 3304 in two dimensions. For example, the diagonal path canreduce or eliminate (i) any vertical play between the first verticalsurface 3342 a of the first projection 3342 of the attachment portion3340 and the first engagement surface 3318 a and (ii) any horizontalplay between the first horizontal surface 3346 a of the third projection3346 of the attachment portion 3340 and the third engagement surface3318 c. The first elongated member 3350 a extends along a direction thatis disposed at an angle of about 10 degrees to about 80 degrees withrespect to the first direction D1 and/or the second direction D2. Insome embodiments, the first elongated member 3350 a extends along adirection that is disposed at approximately 45 degrees with respect tothe first direction D1 and/or the second direction D2. Moreover,wrapping the first elongated member 3350 a around the attachment portion3340 and the securing portion 3304 can reduce or eliminate any playbetween the attachment portion 3340 and the first surface 3304 a of thesecuring portion 3304. The first recess 3312 a can extend through thesecuring portion 3304 along a direction that is generally parallel tothe diagonal path across which the first elongated member 3350 a extendssuch that the first recess 3312 a guides the first elongated member 3350a along the desired diagonal path. In some embodiments, a secondelongated member (not depicted) is wrapped around the securing portion3304 and the attachment portion 3340 such that the second elongatedmember is positioned within a second recess 3312 b in the securingportion 3304 and extends across the attachment portion 3340, through anopening in the attachment portion 3340, and through the opening 3314 inthe securing portion 3304.

In some embodiments, securing the attachment portions 3340 of theappliance to the securing portions 3304 of the fixture 3300 can causethe anchor of the appliance to substantially conform to the body portion3302 of the fixture 3300. Additionally or alternatively, fasteners(e.g., ligature wires, clamps, etc.) may be used to cause the anchor ofthe appliance to substantially conform to the body portion 3302 of thefixture 3300. Moreover, fasteners other than ligature wire may be usedto manipulate the appliance into the 3D configuration and/or secure theappliance to the fixture 3300. For example, a clip, a clamp, a positivemold, a pin, a screw, and/or other fasteners can be used.

The fixture 3300 can be manufactured based on a heat treatment fixturedigital model. For example, the digital model or associated data can beprovided to a fabricating system to produce a physical model based onthe digital model. In one example, the digital model and/or data can beused to 3D print a model of the fixture 3300 in wax. The wax model maythen be used to investment cast the fixture 3300 in brass or othersuitable material. In some embodiments, the fixture 3300 can be 3Dprinted directly in brass or other suitable material (e.g., stainlesssteel, bronze, a ceramic or other material that tolerates hightemperatures required for heat treatment). In such embodiments, thefixture 3300, including the body portion 3302, the securing portion3304, the protrusions 3308, the channels 3310, the recesses 3312, etc.can be designed to prevent or reduce the support material required oncritical surfaces of the fixture 3300 (e.g., the first surface 3302 a ofthe body portion 3302, the first surface 3304 a of the securing portion3304, etc.) to print the fixture 3300.

FIG. 34A depicts an appliance 3400 comprising attachment portions 3402,one of which is engaged with a securing portion 3404 of a fixtureconfigured in accordance with several embodiments of the presenttechnology. For ease of understanding, only one securing portion 3404 ofthe fixture is shown in FIG. 34A. However, the fixture can comprisemultiple securing portions 3404 and/or a body portion (e.g., such asbody portion 3302, etc.). The securing portion 3404 can be configured toreleasably secure an attachment portion 3402, which can facilitatemanipulating the appliance 3400 into a desired 3D configuration. Theappliance 3400 can be shape set (e.g., heat treated, etc.) while securedto the fixture such that the attachment portion remains located at theintended position once the appliance is removed from the fixture. Theintended position at which the securing portion 3404 is configured toretain the attachment portion 3402 can substantially correspond toand/or be derived from a desired position of the tooth to be treated. Inoperation, an arm and/or a connector of the appliance 3400 can move theattachment portion 3402 to the intended position, thereby moving thetooth to the desired position via the attachment portion 3402.

FIG. 34B is an isolated view of the securing portion 3404 of FIG. 34A.The securing portion 3404 can comprise a surface 3405 configured to bepositioned adjacent to and/or in contact with an attachment portion3402. The securing portion 3404 can include one or more protrusions 3406configured to locate the attachment portion 3402 of the appliance 3400at the intended position. For example, the securing portion 3404depicted in FIGS. 34A and 34B includes a first protrusion 3406 a, asecond protrusion 3406 b, a third protrusion 3406 c, and a fourthprotrusion 3406 d (collectively referred to as “protrusions 3406”)extending away from the surface 3405. The protrusions 3406 definechannels therebetween that receive the attachment portion 3402. Thechannels can comprise a first channel 3408 a and a second channel 3408 b(referred to collectively as “channels 3408”). As shown in FIG. 34A, theattachment portion 3402 can be positioned against the surface 3405between the protrusions 3406. The securing portion 3404 can furtherinclude one or more grooves 3410 and/or openings 3412 configured toreceive a fastener at least partially therein. For example, as shown inFIG. 34A, one or more ligature wires 3424 can be positioned within thegrooves 3410 and wrapped around the attachment portion 3402 and thesecuring portion 3404 to secure the attachment portion 3402 to thesecuring portion 3404.

Although the channels 3408 in FIGS. 34A and 34B are defined byprotrusions 3406 extending away from the surface 3405, in someembodiments the securing portion 3404 includes channels 3408 formed byrecesses in the surface 3405. The channels 3408 would thus extend intothe thickness of the securing portion 3404. In some embodiments, thesecuring portion 3404 does not include protrusions 3406 or channels3408. Instead, the securing portion 3404 can comprise printed markings,for example, on the securing portion 3404 that are configured toindicate the intended position of the attachment portion 3400.

According to some embodiments, for example as shown in FIG. 34A, theattachment portion 3402 can be positioned in, at, or adjacent to thesecuring portion 3404 such that the attachment portion 3402 is locatedat its intended position. In some embodiments, the attachment portion3402 is positioned substantially parallel with and/or in contact withthe surface 3405 of the securing portion 3404. In some embodiments, thesecuring portion 3404 and/or protrusions 3406 include one or moreengagement surfaces 3414 configured to facilitate alignment of theattachment portion 3402 with the intended position. For example, thesecuring portion 3404 shown in FIGS. 34A and 34B includes a firstengagement surface 3414 a, a second engagement surface (not visible), athird engagement surface 3414 c, a fourth engagement surface (notvisible), a fifth engagement surface 3414 e, and/or a sixth engagementsurface 3414 f. The first engagement surface 3414 a can be a surface ofthe first protrusion 3406 a, the second engagement surface can be asurface of the second protrusion 3406 b, the third engagement surface3414 c and the fourth engagement surface can be surfaces of thirdprotrusion 3406 c, and the fifth and sixth engagement surfaces 3414 e,3414 f can be surfaces of the fourth protrusion 3406 d.

As shown in FIG. 34A, in some embodiments the attachment portion 3402 ofthe appliance 3400 is generally T-shaped. The attachment portion 3400can comprise a first projection 3416 extending along a first directionD1, a second projection 3418 extending along the first direction D1, athird projection 3420 extending along a second direction D2, and/or afourth projection 3422 extending along the second direction D2(collectively “projections 3416-3422” and “directions D”). In someembodiments, the first direction D1 is generally orthogonal to thesecond direction D2. Although FIG. 34A depicts the attachment portion3402 with four projections 3416-3422, other numbers of projections arepossible. Moreover, the projections 3416-3422 may extend along differentdirections D than the two generally orthogonal directions D1, D2depicted in FIG. 34A. For example, each of the projections 3416-3422 canextend along a unique direction.

To locate the attachment portion 3402 at the intended position, theattachment portion 3402 can be positioned in, at, or adjacent to thesecuring portion 3404 of the fixture such that the attachment portion3402 engages the engagement surfaces 3414. For example, as shown in FIG.34A, the first projection 3416 of the attachment portion 3402 can engagethe first and second engagement surfaces, the second projection 3418 canengage the third and fifth engagement surfaces, the third projection3420 can engage the fourth engagement surface, and the fourth projection3422 can engage the sixth engagement surface. This design of thesecuring portion 3404 allows the attachment portion 3402 to beconstrained in two degrees of freedom, e.g., along the first and seconddirections D1, D2. The securing portions disclosed herein address theselimitations by allowing attachment portions of various widths to bealigned at the intended position.

V. Use of Finite Element Analysis for Design of Orthodontic Appliancesand Treatment Fixtures

As noted previously, in some embodiments, designing and/or fabricatingan orthodontic appliance (or components thereof) or a shape formingfixture (or components thereof) can include using computer-aided orcomputer-automated analyses. In some embodiments, such computer-aidedanalysis can include obtaining one or more digital models and performinga finite element analysis (FEA) using such models. For example, digitalmodels can be obtained that characterize or represent the patient'steeth, gingiva, maxilla, mandible, skull, and/or other anatomicalstructures of the oral cavity (e.g., whether in the OTA, ITA, or FTA),an orthodontic appliance (e.g., in planar form, in desired, 3Dpre-installation form, in a deformed configuration, etc.), and/or ashape forming fixture. As described in more detail below, FEA can beused to evaluate the design and configuration of an orthodonticappliance and/or a shape forming fixture prior to fabricating theappliance and/or shape forming fixture. As such, the designs may becorrected, improved, or otherwise modified based on the evaluationbefore proceeding to fabrication, thereby reducing costly errors andimproving device designs.

Orthodontic appliances of the present technology may have a planar formcorresponding to a flattened or substantially two-dimensional (2D)configuration, a desired, pre-installation form corresponding to asubstantially three-dimensional (3D) configuration of the applianceafter manufacturing (e.g., after shape forming the appliance), and/or aninstalled form corresponding to a substantially 3D configuration of theappliance at the start of treatment once installed in the patient'smouth (e.g., with the appliance coupled to the patient's teeth in an OTAor ITA). According to some embodiments, the pre-installation form of anappliance can be created by coupling an appliance in a planar form (orother intermediate form) to a shape forming fixture setting a shape ofthe appliance while the appliance is coupled to the fixture (e.g., byheat treating the appliance and fixture to form a 3D, contoured shape ofthe appliance). A pre-installation form of the appliance can be createdby any suitable process including, for example, 3D printing anappliance, mechanically deforming an appliance, etc. In someembodiments, a pre-installation form of the appliance can be based on anarrangement of the patient's teeth and/or gingiva in the OTA, the FTA,and/or an ITA. Additionally or alternatively, the pre-installation formof the appliance can have a shape based on a shape of the shape formingfixture. In some embodiments, when the appliance is coupled to the shapeforming fixture, one or more portions of the appliance (e.g., theanchor, the arms, etc.) substantially conforms to a gingival surface ofthe shape forming fixture while certain portions of the appliance (e.g.,attachment portions, etc.) are secured to securing portions of the shapeforming fixture. The gingival surface of the shape forming fixture canbe derived from and/or substantially correspond to the patient's gingivaas represented in the OTA digital model, in the FTA digital model, etc.Each form of the appliance may be virtually represented as a uniquedigital model. For example, the appliance in the planar form may bevirtually represented as a planar appliance digital model.

In some cases, it may be beneficial to evaluate an intended appliancedesign and/or configuration prior to fabricating a physical appliancebased on the intended appliance design and/or configuration to assesshow the physical appliance would perform during treatment. For example,because the pre-installation form of the appliance can be based at leastin part on a desired FTA, the position of one or more portions of theappliance may shift relative to the gingiva once the physical applianceis deformed to be installed in the patient's mouth (e.g., with thepatient's teeth in the OTA or an ITA). As a result, one or more shiftedpositions of the physical appliance may engage the patient's oraltissues and cause pain for the patient that may reduce treatmentcompliance and/or satisfaction. The anchor of the appliance, forexample, may be intended to sit adjacent to and slightly spaced apartfrom the patient's gingiva throughout treatment. In the installed form,the anchor may sit too far away from the gingiva and irritate the tongue(with a lingual appliance), or the anchor member may sit too close tothe gingiva and apply painful pressure to the gingiva (e.g., impinge thegingiva). Thus, one or more systems and methods of the presenttechnology may evaluate the position of the appliance relative to apatient's local anatomy once installed in the patient's mouth, such asthe position of the anchor relative to the gingiva. Based on theevaluation, one or more parameters of the shape forming fixture or theappliance can be modified.

Additionally, when the physical appliance is installed in the patient'smouth, the appliance is deformed from the pre-installation form to theinstalled form and large strain may develop in certain portions of theappliance (e.g., the arms). If strain in the appliance exceeds anelastic limit of the appliance material, plastic deformation may occur,which can alter the forces the appliance is able to apply to the teeth.Thus, one or more systems and methods of the present technology maypredict and/or evaluate potential plastic deformation of the applianceand, based on the prediction and/or evaluation, modify one or moreparameters of the appliance (e.g., geometry of the arms, the geometry ofthe 3D pre-installation form, and/or the locations of the securingmembers on the teeth, etc.) to reduce or eliminate the predicted plasticdeformation.

Orthodontic appliances of the present invention can be configured applya force and/or moment to a patient's tooth to move the tooth from anoriginal position (e.g., OTA or ITA) to a planned position (e.g., ITA orFTA). Various parameters of an orthodontic appliance design such as armgeometry, anchor geometry, material properties, etc. can be selected andadjusted based on an intended force and/or moment to be applied to atooth. In some cases, it may be beneficial to evaluate the forces and/ormoments that an intended appliance design will apply to a patient'steeth before physically manufacturing the appliance to determine whethera physical appliance based on the intended appliance design will performas desired. Thus, one or more systems and methods of the presenttechnology may evaluate forces and/or moments applied to the patient'steeth by an appliance with an intended appliance design and, based onthe evaluation, modify one or more parameters of the appliance and/orshape forming fixture.

To address the foregoing challenges, prior to fabricating the physicalappliance and installing the physical appliance in the patient's mouth,one or more processes may be performed to evaluate an intended appliancedesign by virtually deforming a digital model of the appliance in oneform to produce a digital model of the appliance in another form. Forexample, a digital model of the appliance in a pre-installation form maybe deformed to obtain a digital model of the appliance in an installedform. An output of the virtual deformation can be evaluated to assesswhether the physical appliance will function as intended, and based onthe evaluation of the output, the intended appliance design can bemodified, or a final appliance design can be obtained.

Some or all of the analyses described herein can be performed usingsuitable computing devices (e.g., computing device describedpreviously). The processes can be performed on one computing device orcluster of computing devices working in concert, or various processescan be performed by remote or distributed computing devices, withdifferent steps being performed by different entities and/or differentcomputing devices. For example, some or all of the analysis processesdescribed herein can be performed in a distributed computing environmentin which tasks or modules are performed by remote processing devices,which are linked through a communication network (e.g., a wirelesscommunication network, a wired communication network, a cellularcommunication network, the Internet, a short-range radio network (e.g.,via Bluetooth)). In various embodiments, some or all of the processesdescribed herein can be performed automatically. According to someembodiments, some of the processes described herein may rely at least inpart on one or more inputs from a human operator, such as a clinician ortechnician.

FIG. 35 is a flow diagram of a process 3500 for obtaining a design of anorthodontic appliance. In some embodiments, the process 3500 may includeobtaining an anatomy digital model (e.g., at process portion 3502)representing or characterizing the geometry of one or more anatomicalstructures of the patient (e.g., the teeth, the gingiva, the jaw, theskull, etc.) in an arrangement. The arrangement may be an original tootharrangement (OTA), an intermediate tooth arrangement (ITA), or a finaltooth arrangement (FTA). In some embodiments the anatomy digital modelmay be a modified representation of the patient's teeth and/or gingiva.For example, the anatomy digital model may represent a shape formingfixture based on an OTA and/or a desired FTA. Such shape forming fixturecan include securing portions at positions based at least in part onpositions of the patient's teeth in a desired FTA and a gingiva portionhaving a curvature and/or topography based on a gingiva portion of anOTA digital model or an FTA digital model, for example. The process 3500may include obtaining an appliance digital model (process portion 3504)representing the orthodontic appliance in a specific form. For example,the appliance digital model may be a planar appliance digital model thatrepresents the orthodontic appliance in a substantially flattened or 2Dconfiguration. In some embodiments, the appliance digital modelrepresents the appliance in an intermediate configuration (e.g., priorto shape forming, etc.).

The process 3500 may continue at process portion 3506 with virtuallydeforming the appliance digital model based on the anatomy digitalmodel. The process 3500 may perform the virtual deformation at processportion 3506 by finite element analysis (FEA), finite differencemethodology, finite volume methodology, or any other suitable numericalmethodology. For example, virtually deforming the appliance digitalmodel may include performing an FEA with the appliance digital model andthe anatomy digital model to deform the appliance digital model based ona difference in position between a portion of the appliance digitalmodel and a portion of the anatomy digital model. The process 3500 mayobtain an output of the virtual deformation at process portion 3508 andmay evaluate the output in process portion 3510. The output may comprisethe virtually deformed appliance digital model, the anatomy digitalmodel, and/or data produced by the virtual deformation such asdisplacement, force, strain, stress, and/or relative position.Evaluating the output may comprise performing a quantitative comparisonof the output to a predetermined threshold or parameter. In someembodiments, evaluation of the output may be qualitative. For example, ahuman operator can visually inspect the output. Based on the evaluationof the output performed at process portion 3510, the process 3500 maycontinue with modifying one or more of the previously obtained digitalmodels (process portion 3512). For example, the process 3500 maydetermine that a strain in the appliance digital model exceeds apredetermined threshold and can therefore modify the geometry of one ormore portions of the appliance digital model to reduce the strain thatoccurs in the appliance when the appliance is deformed. Based on theevaluation of the output 3510, the process 3500 may continue to processportion 3514 and output one or more previously obtained digital models.The digital model(s) output by process portion 3514 may be used tofabricate a physical appliance and/or fixture, as previously described.

FIG. 36 illustrates an example process 3600 for evaluating anorthodontic appliance design. In some embodiments, each of the processportions of the process 3600 can be executed automatically or manually,by human operator, for example. The process 3600 may begin at processportion 3602 with obtaining a shape forming fixture digital model. Anexample of a shape forming fixture model 1200 is shown in FIG. 12,described above. The shape forming fixture digital model may correspondto and/or be derived from an OTA digital model and/or a desired FTAdigital model. In some embodiments, the shape forming fixture digitalmodel can have with certain modifications relative to an anatomy digitalmodel (e.g., enlarging the gingiva, replacing securing members withsecuring portions, etc.). At process portion 3604, a planar appliancedigital model may be obtained. An example of a planar appliance digitalmodel 1500 is shown in FIG. 15, described above. The planar appliancedigital model may have a substantially flattened or 2D configuration andmay virtually represent the appliance design comprising an anchor, aplurality of arms, a plurality of attachment portions, etc. In someembodiments, the planar appliance digital model can include a thicknessdimension, which can be uniform over the appliance or may vary overdifferent portions of the appliance. The process 3600 may continue atprocess portion 3606 with performing a first FEA with the planarappliance digital model based on the shape forming fixture digitalmodel. For example, an output of the first FEA can comprise an intendedappliance digital model, in which the planar appliance digital model hasbeen substantially conformed to the fixture digital model. The intendedappliance digital model can comprise a contoured, 3D appliance having ashape based on a shape of the fixture digital model. In some examples,performing the first FEA can comprise deforming the planar appliancedigital model based on a feature (e.g., securing portions, gingivaportion, etc.) of the fixture model. For example, attachment portions ofthe planar appliance digital model can be virtually mated tocorresponding securing portions of the fixture digital model. In someembodiments, the process 3600 may perform the first FEA at processportion 3606 using suitable commercial FEA software (e.g., Abaqus,Ansys, etc.) and/or suitable proprietary FEA software.

Although some embodiments describe using the shape forming fixturedigital model to generate a contoured, 3D configuration of the appliancedigital model, in some embodiments an FTA digital model (e.g., FTAmodels 800 or 1100 described above) can be used. For example, a planarappliance digital model can be deformed to conform to a surface of anFTA digital model, without the need for the shape forming fixturedigital model. Additionally or alternatively, other anatomy digitalmodels or boundary conditions can be used to deform a digital model ofan appliance an intermediate form to obtain a digital model of theappliance in the intended form. In some embodiments process portions3602-3606 can be omitted from the process 3600 and an intended appliancedigital model can be obtained (process portion 3608) without performingthe first FEA.

In some embodiments, performing the first FEA at process portion 3606may include meshing one or more of the digital models, wherein meshingcomprises discretizing a digital model into a plurality of finiteelements and a plurality of nodes. Meshing may be performed manually,such as by human operator providing inputs to suitable software, and/orautomatically using suitable software. Suitable software may includecommercial meshing software (e.g., Hypermesh®), commercial FEA softwarewith meshing capabilities (e.g., Abaqus, Ansys, etc.), and/orproprietary meshing software. The finite elements may have adimensionality based on a geometry of the digital model, including, butnot limited to, 2D (e.g., triangular, quadrilateral, etc.) or 3D (e.g.,tetrahedral, quadrilateral, etc.) elements. For example, the finiteelements for the planar appliance digital model may comprise hexahedral3D elements. Element parameters (e.g., element type, element order,number of integration points, hourglass control, etc.) may be selectedto control and/or modify the accuracy and stability of the FEA. In someembodiments, performing the FEA may include meshfree techniques such aselement-free Galerkin process, generalized-strain mesh-free formulation,isogeometric analysis, or the process of external approximations.

Performing the first FEA at process portion 3606 may include assigningmaterial properties (e.g., Young's modulus, Poisson's ratio, density,etc.) to the planar appliance digital model and the shape formingfixture digital model. For example, material properties for nitinol maybe assigned to the planar appliance digital model, such as a Young'smodulus between about 28 GPa and 83 GPa. In some embodiments, the shapeforming fixture model may be represented as a deformable component withmaterial properties for brass, such as a Young's modulus between about100 GPa and 130 GPa. In some embodiments, the shape forming fixturedigital model may be represented as a rigid component such that theshape forming fixture digital model does not deform during the firstFEA. The shape forming fixture digital model may be represented as arigid component by assigning an artificially large Young's modulus tothe shape forming fixture digital model. The process 3600 may obtain thematerial properties from a database and/or the material properties maybe entered manually.

In some embodiments, performing the first FEA (process portion 3606) mayinclude defining a contact interaction between at least one portion ofthe appliance digital model and at least one portion of the shapeforming fixture digital model. Defining the contact interaction mayinclude creating a first contact surface by selecting digital nodes,elements, and/or surfaces of the planar appliance digital model. Anothercontact surface may be created by selecting digital nodes, elements,and/or surfaces of the shape forming fixture digital model. Defining thecontact interaction may further comprise defining a contact formulationto govern the contact interaction between the contact surfaces. The typeof contact formulation (e.g., bonded, frictional, frictionless, etc.)may be selected from a database of contact formulations and/or or thecontact formulation may be entered manually. The process may furthercomprise entering relevant parameters of the contact formulationincluding, but not limited to, a coefficient of friction, a penaltycontact stiffness, and/or a nodal search distance. For example, in someembodiments a bonded contact interaction can be defined between anattachment portion of the appliance digital model and a channel, asurface, and/or a protrusion of a securing portion of the shape formingfixture digital model. In some embodiments, a sliding contactinteraction can be defined between an attachment portion of theappliance digital model and a securing portion of the shape formingfixture digital model. For example, a sliding contact interaction can bedefined to simulate interplay between an attachment portion and asecuring member.

Performing the FEA in process portion 3606 may include assigningboundary conditions to at least one of the digital models. In someembodiments, the boundary conditions may include a constraint to preventtranslation and/or rotation of one or more portions of one or moredigital models. For example, the boundary conditions may include aconstraint of the shape forming fixture digital model and one or moreattachment portions of the planar appliance digital model. In additionor alternatively, the boundary conditions may include a non-zero force,moment, displacement, and/or rotation. For example, to virtually deformthe planar appliance digital model into a contoured or 3D digital modelrepresenting the pre-installation form of the appliance, a non-zerodisplacement may be applied to a portion of the anchor of the planarappliance digital model. The non-zero displacement can correspond to adistance between the anchor member and a distal region of the gingivaportion of the fixture digital model when the attachment portions of theplanar appliance digital model are within the securing portions of theshape forming fixture digital model. In some embodiments, the planarappliance digital model can be virtually deformed into a contoured or 3Ddigital model representing the pre-installation form of the appliance byapplying a non-zero displacement to an attachment portion of the planarappliance digital model such that the attachment portion is positionedwithin a corresponding securing portion 1202 of the shape formingfixture digital model. In addition, or alternatively, a non-zerodisplacement can be applied to an attachment portion and/or arm of theplanar appliance digital model such that the attachment portion and/orarm is tangent to a base plane (e.g., the broad surface, etc.) of acorresponding securing portion of the shape forming fixture digitalmodel.

In some embodiments, performing the FEA in process portion 3606 mayinclude defining one or more analysis parameters such as analysis type(e.g., static or dynamic), geometric linearity, integration scheme(e.g., implicit, explicit), simulation duration, incrementation size,and/or incrementation control. Performing the FEA may include runningthe FEA until an exit condition is reached. For example, running the FEAmay include applying a non-zero displacement to the planar appliancedigital model, wherein the exit condition is reached once the entiremagnitude of the non-zero displacement has been applied.

Referring back to FIG. 36, the process 3600 may continue at processportion 3608 with obtaining an intended appliance digital modelvirtually representing the appliance in a pre-installation form. FIG. 37depicts an example of an intended appliance digital model 3702 matedwith a shape forming fixture model 3704 as a result of the first FEA(process portion 3606). The intended appliance digital model 3702obtained in process portion 3608 can be obtained from the first FEAperformed in process portion 3606 of the process 3600. In someembodiments, an intended appliance digital model 3702 representing acontoured or 3D configuration of the appliance after manufacturing canbe obtained without performing a first FEA. For example, an intendedappliance digital model 3702 can be obtained directly from CAD softwaresuch as Solidworks®, Autodesk® Inventor, Autodesk® MeshMixer, Creo®,etc. In addition, or alternatively, an intended appliance digital model3702 can be obtained from a scan of a physical representation of anappliance such as a fabricated appliance, an appliance mold, etc. Atprocess portion 3610 an OTA digital model may be obtained that virtuallyrepresents the patient's teeth, gingiva, and/or other anatomicalstructures in an original arrangement. For example, an OTA digital modelwith securing members attached thereto, such as digital model 1000, canbe used. In some embodiments, the OTA digital model can comprise amodified representation of the patient's teeth and/or gingiva. Forexample, the OTA digital model can have similar features as the shapeforming fixture (e.g., securing portions with channels and/orprotrusions, a gingival portion, a stabilizing crossbar, etc.) in placeof or in addition to a virtual representation of the patient's actualteeth and/or gingiva. For example, in some embodiments, securingportions located at positions of a patient's teeth in an originalarrangement can replace a virtual representation of the patient's actualteeth in an OTA digital model. According to some embodiments, the OTAdigital model can comprise a dataset comprising position datacharacterizing the spatial coordinates of a patient's teeth in anoriginal arrangement.

Referring back to FIG. 36, the process 3600 may continue with performinga second FEA with the intended appliance digital model (e.g., digitalmodel 3702) and the OTA digital model (e.g., digital model 700, 1000,etc.) at process portion 3612 to produce a deformed intended appliancedigital model representing the appliance in an installed form. FIG. 38illustrates an example of a digital model 3800 that includes a deformedintended appliance digital model 3802 mated with an OTA digital model3804. The OTA digital model 3804 can be similar to any other OTA digitalmodel disclosed herein (e.g., OTA digital model 700, OTA with securingmember digital model 1000, etc.). As shown in FIG. 38, the deformedintended appliance digital model 3802 can virtually represent theappliance in an installed form in the patient's mouth (e.g., in the OTAor ITA). For example, via the second FEA, the intended appliance digitalmodel 3702 (e.g., characterizing the appliance in a pre-installationform) can be virtually deformed into an installed form in which theappliance is mated to a patient's teeth in the OTA (or ITA), asreflected in the OTA digital model 3804. This virtual deformation canproduce the deformed intended appliance digital model 3802, which caneffectively model the real-world behavior of a fabricated appliance wheninstalled within a patient's mouth. As such, evaluation of the deformedintended appliance digital model 3802 allows a human operator and/or anautomated process to assess and/or predict operation and behavior of theappliance when installed within the patient's mouth.

In some embodiments, performing the second FEA can include discretizingthe digital model(s), assigning material properties, defining anycontact interactions, assigning boundary conditions, defining anyanalysis parameters, and/or running the FEA until an exit condition isreached as previously described. For example, assigning boundaryconditions to perform the second FEA may include determining adisplacement of each tooth between the FTA and OTA. As previouslydescribed, the displacement of a tooth can be defined using six degreesof freedom by calculating the difference between the location of eachtooth in the FTA data and the OTA data. Assigning the boundaryconditions can include assigning the displacement of each tooth betweenthe FTA and OTA to a corresponding attachment portion of the intendedappliance digital model 3702. Assigning the boundary conditions maycomprise assigning constraints to prevent rotation and/or translation ofthe OTA digital model 3804 and/or one or more portions of the intendedappliance digital model 3702.

Referring back to FIG. 36, at process portion 3614 the process 3600 mayobtain the deformed intended appliance digital model (see, for example,FIG. 38), and/or an analysis result. The deformed intended appliancedigital model 3802 and/or the analysis result can be obtained from thesecond FEA. The deformed intended appliance digital model 3802 mayvirtually represent the appliance in an installed form once it has beeninstalled into the patient's mouth (e.g., with the appliance coupled tothe patient's teeth in an OTA or ITA). The analysis result can compriseoutput data from the second FEA. For example, the analysis result may bea measure of position, displacement, rotation, force, moment, stress, orstrain in one or more of the digital models used in the second FEA. Theprocess 3600 may continue at process portion 3616 with evaluating theanalysis result. In some embodiments, evaluating the analysis resultincludes comparing the analysis result to one or more predeterminedthresholds. Based on the evaluation of the analysis result, the process3600 may continue to process portion 3618 and modify the planarappliance digital model and/or the shape forming fixture digital model.

In various embodiments, modifying the appliance digital model (e.g., theplanar appliance digital model, the intended 3D appliance digital model,etc.) can include modifying the particular shape and/or configuration ofan anchor and/or arms of the appliance, the geometry of the 3Dpre-installation form of the appliance, and/or the locations of thesecuring members on the teeth. For example, features of the arm(s) thatcan be modified include but are not limited to, the overall length ofthe arm, the shape or configuration of the biasing portion, the shape orconfiguration of the bracket connector, the width dimension of one ormore sections of the arm, the thickness dimension of one or moresections of the arm, or the like. Features of the anchor that can bemodified include, but are not limited to the shape, length, thickness,depth, or other properties of the anchor. In some embodiments, a humanoperator may manually select or revise the design and configuration ofthe anchor and/or arms as desired. In some embodiments, one or more ofthe arms can be replaced based on a pre-populated library of armdesigns. In some embodiments, fully or partially automated modificationof the appliance digital model or the shape forming fixture digitalmodel can be reviewed and/or modified by an operator based on relevantcriteria.

FIG. 39 illustrates an example of an analysis result of a deformedintended appliance digital model 3802 in a configuration mated to apatient's teeth, as reflected in the OTA digital model 3804. Theanalysis result can include a measure of strain in the appliance digitalmodel 3802. The measure of strain may comprise, for example, a singlemaximum strain in the appliance, a volume of elements exceeding a strainthreshold, and/or an average strain of a portion of the appliance. Asdepicted in FIG. 39, the measure of strain may be displayed by theprocess 3600 as a heat map superimposed over the appliance digital model3802. Such a heat map (or other graphical representation) can visuallyindicate the strain at different regions of the appliance digital model3802. In some embodiments, the measure of strain may be a number and/ora set of numbers. The process 3600 may compare the measure of strain toa predetermined maximum strain threshold in process portion 3616. Insome embodiments, the predetermined maximum strain may be an elasticlimit of the appliance material. For example, the predetermined maximumstrain for nitinol may between about 4% to about 10%. If the measure ofstrain exceeds the predetermined maximum strain threshold, the process3600 may proceed to process portion 3618 and modify the planar appliancedigital model. Modifying the planar appliance digital model may include,for example, increasing the thickness of one or more portions of theappliance, selecting a different geometry of an arm or anchor portion ofthe appliance, etc.

In some embodiments, the analysis result may comprise a force and/ormoment in order to evaluate a force and/or moment the appliance appliesto a patient's tooth. For example, the analysis result can be a reactionforce and/or moment measured at a portion of the anchor of the appliancedigital model 3802, a securing member of an OTA digital model 3804, atooth of the OTA digital model, or any other suitable location. Thelocation the force and/or moment is measured from can be based, at leastin part, on the boundary conditions assigned in the second FEA. In someembodiments, evaluating the analysis result (process portion 3616)comprises comparing the force and/or moment to a predetermined value. Insome embodiments, the predetermined value may correspond to an intendedforce and/or moment. A difference between the measured and intendedforce and/or moment can be obtained and evaluated to determine if aphysical appliance based on the intended appliance design willsufficiently apply the intended force and/or moment and perform asintended. In some embodiments, the predetermined value can be a safetythreshold corresponding to a maximum allowable force for the applianceand/or the patient's anatomy. According to some embodiments, thepredetermined value is a minimum force and/or moment, a range ofallowable forces and/or moments, or any other suitable metric. Based onthe comparison of the force and/or moment to the predetermined value,the process 3600 may modify one or more parameters of the planarappliance digital model, the shape forming fixture digital model, theintended appliance digital model 3700, or another suitable digitalmodel.

Another example of an analysis result includes identifying portions ofthe appliance that may impinge on a patient's gingiva. For example, asshown in FIG. 39, in region 3902, a portion of the appliance digitalmodel 3802 has penetrated beneath a gingival surface of the OTA digitalmodel 3804. This may occur as a result of deformation of the model fromthe intended appliance digital model 3702 to the deformed appliancedigital model 3802 described previously. The intersection shown inregion 3902 can indicate an area at which a real-world fabricatedappliance is at risk of contacting the patient's gingiva when installed.Such contact can be uncomfortable and irritate the patient's gingiva.Accordingly, as a result of identifying such a contact point, theappliance design may be modified (e.g., by modifying the planarappliance digital model), the pre-installation form of the appliance maybe modified (e.g., by modifying the shape forming fixture model), or anyother suitable modifications, corrections, or compensations may be made.

FIG. 40 illustrates another example of an analysis result based onassessment of the relative positions of the deformed appliance digitalmodel 3802 and the OTA digital model 3804. For example, as shown in FIG.40, a portion of the appliance digital model 3802 is spaced apart from agingival surface of the OTA digital model 3804 by a local distance 4000due to a shape set form of the appliance. Too large of a gap between theappliance the patient's gingiva can irritate the patient's tongue andcause pain and/or discomfort for the patient. Therefore, in someembodiments, the analysis can include determining whether a localdistance 4000 is greater than a predetermined maximum distancethreshold. In the example shown in FIG. 40, the analysis result cancomprise a local distance 4000 between a portion of the deformedintended appliance digital model 3802 and a portion of the lingualsurface of the patient's gingiva of the OTA digital model 3804 thatexceeds a predetermined maximum distance threshold. In some examples,the maximum distance threshold for a local distance between a portion ofthe deformed intended appliance digital model and a portion of thelingual surface of the patient's gingiva may be between about 0 mm andabout 5 mm. If the local distance 4000 is greater than the maximumdistance threshold, the process 3600 may modify one or more digitalmodels (process portion 3618) to thereby modify the relative positionsof the appliance in the installed form and the patient's gingiva. Forexample, the thickness of the gingival surface of the shape formingfixture digital model can be increased and/or decreased at one or morelocations. The process 3600 may repeat with the modified digitalmodel(s) to determine if the local distance 4000 falls below the maximumdistance threshold and whether the modified digital model(s) are morefavorable design(s).

It may be favorable to space an anchor of an appliance apart from apatient's gingiva to minimize irritation of the patient's gingiva due tothe appliance. Consequently, in some embodiments, the analysis resultcan comprise a local distance 4000 between a portion of the deformedintended appliance digital model 3802 and a portion of the lingualsurface of the patient's gingiva of the OTA digital model 3804 that isless than a predetermined minimum distance threshold. In some examples,the minimum threshold may be between about 0.00 mm and 0.5 mm. If thelocal distance 4000 is less than the minimum distance threshold, theprocess 3600 may modify one or more digital model(s) (process portion3618). For example, the thickness of the gingival surface of the shapeforming fixture digital model 1200 may be increased and/or decreased atone or more locations. Such a modification may alter thepre-installation form of the appliance. The process 3600 may repeat withthe modified digital model(s) to determine if the local distance fallsabove the minimum threshold.

According to some embodiments, the process 3600 can iteratively repeatuntil a favorable appliance design is obtained. For example, FIG. 41depicts four deformed intended appliance digital models 4100 a, 4100 b,4100 c, and 4100 d mated to an OTA digital model 4104 representing thepatient's teeth in an original arrangement. A first appliance digitalmodel 4100 a has penetrated a gingival surface of the OTA digital model4104 in a first intersecting region 4102 a as a result of the secondFEA. The process 3600 can modify one or more digital model(s) based onthis analysis result (process portion 3618) and repeat process portions3602 through 3616 with the modified digital model(s) until a finalizedappliance design is obtained. For example, FIG. 41 shows a secondappliance digital model 4100 b that penetrates a gingival surface of theOTA digital model 4104 to a lesser extent than the first appliancedigital model 4100 a, forming a second intersection region 4102 b thatis smaller than the first intersection region 4102 a. A third appliancedigital model 2022 c forms a third intersection region 4102 c that issmaller than the first and second intersection regions 4102 a, 4102 b. Afourth appliance digital model 2502 d depicted in FIG. 41 does notpenetrate a gingival surface of the OTA digital model 4104 and may be afavorable appliance design. Based on the favorable fourth appliancedigital model 2502 d, the process 3600 can stop iteratively repeatingand select a finalized appliance design. In some embodiments, a humanoperator can select a finalized appliance design. In some embodiments, afinalized appliance design can be selected automatically and/or by ahuman operator based on a quantitative metric such as, but not limitedto, a change in an analysis result between iterations, a comparison ofan analysis result to a predetermined threshold or parameter, etc. Inaddition, or alternatively, the process 3600 may stop repeating andselect a finalized appliance design if a predetermined maximum number ofiterations has been reached.

In some embodiments, the fixture digital model can be modified based ona final appliance design. For example, the gingiva portion of thefixture digital model can be modified such that the a lingual surface ofthe gingiva portion is tangent to the gingival-facing surface of theappliance when attachment portions of the appliance are positionedwithin and tangent to a base plane of securing portions of the fixturedigital model.

Upon selection of a final appliance design and/or a final shape formingfixture design, the process 3600 can continue to process portion 3620and output the planar appliance digital model, the shape forming fixturedigital model, and/or the intended appliance digital model 3702. Basedon the output in process portion 3620, the appliance and/or the shapeforming fixture can be fabricated, for example using any of thetechniques described previously herein.

VI. Selected Devices, Systems, and Methods for Manufacturing OrthodonticAppliances Based on Overcorrection and/or Compensation Parameters

As previously described, the manufacturing process to create anorthodontic device (e.g., an orthodontic appliance or fixture) accordingto embodiments of the present technology can include obtaining datacorresponding to an OTA of a patient, and then using the data to developan FTA model in which the patient's teeth are in an optimal position.The FTA model can be used as a basis for creating a fixture (e.g., aheat treatment fixture) that generally corresponds to the FTA, but withone or more modifications (as discussed elsewhere herein). The fixturecan then be used to form a 3D configuration of the appliance (e.g., acurved or contoured configuration of the appliance able to urge teethfrom the OTA toward the FTA when installed in a patient's mouth). Forexample, as described elsewhere herein, a substantially planarconfiguration of the appliance may be manipulated and/or disposed overthe fixture and then heat treated on the fixture such that the applianceassumes a 3D shape that generally conforms to the fixture.

Manufacturing the appliance in such a manner should enable the applianceto precisely replicate the FTA described above and, when installed,reposition a patient's teeth from the OTA to the desired FTA. However,in practice, certain factors may cause there to be a discrepancy betweenthe desired FTA and the actual final arrangement of the patient's teethafter repositioning via the appliance. As described in more detailbelow, this discrepancy can be due to: (a) implementation considerations(e.g., a minimum threshold force needed to move the patient's teeth,and/or free play or tolerance between the appliance and securingmember), (b) material properties of the appliance (e.g., plasticdeformation, hysteresis, etc.), (c) irregularities associated with themanufacturing process, and/or (d) expected teeth movement (e.g.,relapse) after repositioning. To mitigate these issues, embodiments ofthe present technology can account for these discrepancies and modifydesign parameters (e.g., via overcorrection or compensation) of thefixture and/or appliance during or prior to manufacturing thereof.

A person of ordinary skill in the art will recognize that whileembodiments of the present technology related to overcorrection orcompensation are described below as individual parameters or factors,any of the factors described may be combined in a single embodiment. Forexample, design or manufacturing of an appliance and/or fixture mayconsider both the minimum threshold force needed to move the patient'steeth as well as irregularities associated with the manufacturingprocess.

C. Considerations Related to Orthodontic Device Implementation

As previously described, orthodontic appliances of the presenttechnology are generally designed and manufactured based at least inpart on the forces (e.g., load/moment/magnitude and/or direction) neededto reposition a patient's teeth (e.g., individual teeth) from the OTA toa desired or optimal FTA. In some embodiments, these appliances mayconsider external factors acting thereon (e.g., the minimum thresholdforce needed to move a patient's teeth and/or the free play between theappliance and securing members), which in turn affect the necessaryforce(s) that the appliance and/or one or more portions thereof mustprovide on the patient's teeth to cause the desired repositioning to theFTA.

1. Minimum Threshold Force to Move a Patient's Teeth

As previously described, appliances of the present technology areconfigured to move a patient's teeth from the OTA along a path to adetermined FTA. More specifically, individual arms of the appliance areconfigured to move a respective patient's tooth along a respective pathfrom an original position to a respective final position. The forceapplied to a patient's teeth via the appliance, or in some embodimentsthe force applied to a patient's tooth via a corresponding arm of theappliance, is generally highest at or near the OTA, when the applianceis in a loaded or stressed state, and decreases as the patient's teethapproach the FTA, when the appliance is in an unloaded or unstressedstate. Accordingly, when the patient's teeth approach the FTA, theappliance will generally be applying some minimal force to the teeth.However, due to various external factors, such as the root of aparticular tooth or positioning of a tooth within the gingiva, there canbe a minimum threshold force that must be overcome to move each tooth.That is, a force applied via an arm of the appliance on the tooth thatis less than the minimum threshold force will not move the tooth.Therefore, if an appliance in its unloaded state is manufactured toresemble or otherwise correspond to the FTA without considering thisminimum threshold, movement of the patient's teeth may cease prior toactually reaching the FTA.

To further illustrate this point, FIG. 42 is a plot 4200 showing therelationship between force applied to a patient's teeth on the y-axis,and positioning of the patient's teeth on the x-axis. As shown in FIG.42, line 4210 corresponds to a minimum threshold force needed to move apatient's teeth, line 4220 corresponds to varying forces applied, e.g.,via a first appliance, to the patient's teeth during movement from theOTA to a first final tooth arrangement (FTA₁), and line 4230 correspondsto varying forces applied, e.g., via a second appliance, to thepatient's teeth during movement from the OTA to a second final tootharrangement (FTA₂). In some embodiments, the minimum threshold force maybe at least about 5 grams-force (GF), 10 GF, 15 GF, 20 GF, 25 GF, or 50GF. The first appliance has an unloaded or unstressed state thatcorresponds to the first final tooth arrangement (FTA₁), which is anoptimal tooth arrangement determined for the patient, and the secondappliance has an unloaded state that corresponds to the second finaltooth arrangement (FTA₂) different than the first final tootharrangement (FTA₁).

As shown in FIG. 42, lines 4220, 4230 indicate a generally linearrelationship between force applied to the patient's teeth andpositioning thereof. However, a person of ordinary skill in the art willappreciate that in some embodiments the relationship between the appliedforce and positioning of the patient's teeth may be non-linear (e.g.,exponential, logarithmic, etc.). Additionally or alternatively, in someembodiments the relationship between force applied to the patient'steeth and positioning thereof can be linear, non-linear, and/or constantdepending on the strain of the appliance of portions thereof (e.g., thearm(s) of the appliance). For example, with regard to an appliance orarm comprising nitinol, the force applied to the patient's teeth via thenitinol appliance may be constant or nearly constant during a firstportion of teeth movement and have a linear of non-linear relationshipto the position of the patient's teeth during a second, differentportion of teeth movement.

As indicated by line 4220 of FIG. 42, the first appliance (manufacturedto have an unloaded configuration corresponding to the first final tootharrangement (FTA₁)) will cause the patient's teeth to reposition fromthe OTA along a path toward the first final tooth arrangement (FTA₁).Such an appliance, when implanted within a patient's mouth and securedto securing members adhered to the patient's teeth (as previouslydescribed), will transition from a loaded configuration generallycorresponding to the OTA toward an unloaded configuration generallycorresponding to the first final tooth arrangement (FTA₁). However, dueto the minimum threshold force (T_(MIN)) needed to move the patient'steeth (as shown by line 4210), the first appliance will be unable tomove the patient's teeth all the way to the first final tootharrangement (FTA₁), and instead will move the patient's teeth only untilthe force provided via the appliance is equal to the minimum thresholdforce (T_(MIN)), as represented by position (Pi) in FIG. 42.

Embodiments of the present technology can mitigate the above describedissues by considering the minimum threshold force (T_(MIN)) whendesigning the orthodontic appliance. In some embodiments, an appliancemay be designed and/or manufactured to have a second final tootharrangement (FTA₂) in its unloaded configuration that is different thatthe first final tooth arrangement (FTA₁). When implanted within apatient's mouth and secured to securing members adhered to the patient'steeth, the second appliance is configured to reposition the patient'steeth from the OTA toward and/or to the first final tooth arrangement(FTA₁). In such embodiments, the second appliance is designed to providethe minimum threshold force (T_(MIN)) on the patient's teeth when thesecond appliance, which has an unloaded configuration corresponding tothe second final tooth arrangement (FTA₂), assumes a configurationgenerally corresponding to the first final tooth arrangement (FTA₁). Asshown in FIG. 42, the second appliance can be manufactured to have anunloaded configuration generally corresponding to the second final tootharrangement (FTA₂). When implanted within a patient's mouth and securedto corresponding securing members, the second appliance will cause thepatient's teeth to reposition from the OTA along a path toward thesecond final tooth arrangement (FTA₂), as indicated by line 4230. Due tothe minimum threshold force (T_(MIN)), movement of the patient's teethvia the second appliance ceases when the second appliance generallyassumes the first final tooth arrangement (FTA₁) and is providing aforce on the patient's teeth approximately equal to the minimumthreshold force (T_(MIN)). As shown in FIG. 42, such an appliance isconfigured to apply a nonzero force on the patient's teeth when theybecome repositioned to the first tooth arrangement (FTA₁). The nonzeroforce may be (i) at least about 5 GF, 10 GF, 15 GF, 20 GF, 25 GF, or 50GF, and/or (ii) no more than 500 GF, 400 GF, 300 GF, 250 GF, 100 GF, or50 GF.

The above description regarding the minimum threshold force applies tothe appliance and patient's teeth generally, but the same or similarprinciples also apply to individual arms of the appliance and individualteeth of the patient. For example, each arm of the appliance may beconfigured to move a corresponding patient tooth such that the forceprovided via the arm is equal to the minimum threshold force (T_(MIN))when the position of the arm generally corresponds to that of acorresponding arm in the first final tooth arrangement (FTA₁). Moreover,the minimum threshold needed to move a particular tooth may be slightlydifferent from other teeth, e.g., depending on the type of tooth (e.g.,molar or incisor), the position of the tooth (e.g., relative to theadjacent gingival surface), and/or other factors. As such, the distinctminimum threshold force for individual teeth may each be accounted forwhen designing the corresponding portions (e.g., arms, biasing portions,attachment portions, etc.) of the appliance.

FIG. 43 is a flow diagram of a method 4300 for determining a datasetassociated with an arrangement of an orthodontic device, in accordancewith embodiments of the present technology. The method 4300 includesobtaining data (e.g., a first input) corresponding to an OTA of apatient (process portion 4302), and obtaining data (e.g., a secondinput) corresponding to a first FTA of the patient (process portion4304). As described elsewhere herein, the OTA can be based on a scan ofthe patient's teeth, and the FTA can be determined and/or provided by anoperator (e.g., a clinician, orthodontist, or technician) based on theOTA and a desired optimal positioning of the teeth.

The method 4300 can further include determining data (e.g., a thirdinput) corresponding to a second FTA (different than the first FTA),based in part on a minimum threshold force needed to move at least onetooth of the patient (process portion 4306). The minimum threshold forcemay be a predetermined parameter, in that the minimum threshold force isknown or can be determined prior to manufacturing of the device. In someembodiments, the minimum threshold force may correspond to amodification applied generally to the appliance (e.g., the samemodification is applied to each individual arm), or a plurality ofdistinct modifications applied to each individual arm of the appliance.Additionally or alternatively, the minimum threshold may be determinedbased on factors common to all patients generally or on factors uniqueto a particular patient. For example, in some embodiments the minimumthreshold considered may be based on the general anatomy of human teeth,e.g., with molars or larger teeth having a greater minimum thresholdthan that of incisors or smaller teeth. As another example, in someembodiments the minimum threshold considered may be based on thepatient's particular gingiva (e.g., the gingival surface) surroundingindividual ones of the patient's teeth.

In some embodiments, the method 4300 may omit process portion 4306 andonly include a single FTA that considers the minimum threshold force. Insuch embodiments, the method 4300 may include obtaining first datacorresponding to an OTA of a patient, and providing second datacorresponding to an FTA of the patient, where the second data is basedat least in part on a minimum threshold force. In some embodiments, themethod 4300 can further comprise manufacturing the fixture and/or theappliance according to at least the data corresponding to the secondFTA. Such manufacturing of the fixture and/or the appliance cancorrespond to the manufacturing processes described elsewhere herein.

2. Free Play Between the Appliance and Securing Member

As previously described, appliances of the present technology areconfigured to move a patient's teeth from the OTA along a path to adetermined FTA. More specifically, individual arms of the appliance areconfigured to move a respective patient's tooth along a respective pathfrom an original position to a respective final position. As alsopreviously described, the individual arms are attached to acorresponding securing member (e.g., a bracket) adhered to individualteeth of the patient. Accordingly, the force applied via the individualarms of the appliance is provided to the corresponding securing member,and therein to the corresponding individual patient's tooth to causerepositioning. In this regard, because the securing members are aseparate component from the appliance, there will often be some freeplay (e.g., gap, wiggle, or misfit, for example due to manufacturingtolerances) between each individual arm and the corresponding securingmember. In some embodiments, the free play is the same for eachindividual arm and corresponding securing member. Moreover, in someembodiments the free play is different for at least one of theindividual arms and corresponding securing member relative to otherindividual arms and corresponding securing members. As a result of thefree play, the force provided via the individual arm may not be entirelytransferred to the corresponding tooth because a portion of the force islost via the free play. For example, if an individual arm is configuredto move the corresponding tooth a given distance in a particulardirection (e.g., the mesial, distal, occlusal, gingival, buccal, and/orlingual direction) and/or a given angle of rotation about a particularaxis (e.g., about the mesiodistal axis, occlusogingival axis, and/orbuccolingual axis), the free play can prevent the corresponding toothfrom moving the full distance and/or the full angle of rotation.

FIG. 44A is a perspective view of a securing member 4400, and FIG. 44Bis a perspective view of a portion of an arm 4430 of an orthodonticappliance coupled to the securing member 4400 shown in FIG. 44A, inaccordance with embodiments of the present technology. As shown in FIG.44A, the securing member 4400 includes (i) a body region 4405 having aback side or surface 4410 to be attached to a patient's tooth, (ii) aslot or recess 4412 within the body region 4405 and configured toreceive a portion of an orthodontic appliance or arm, and (iii) amoveable clip portion 4420 coupled to the body region 4405 configured tosecure the portion of the appliance or arm 4430 when positioned withinthe slot 4412. The slot 4412 can form a three-sided or U-shaped opening.As shown in FIG. 44B, the arm 4430, or more particularly an attachmentportion 4440 of the arm 4430, is disposed within the slot 4412. As alsoshown in FIG. 44B, the x-axis may generally correspond to thebuccolingual axis, the y-axis may generally correspond to theocclusogingival axis, and the z-axis may generally correspond to themesiodistal axis.

FIG. 44C is an enlarged cross-sectional side view of the securing member4400 and arm 4430 shown in FIG. 44B, and is meant to further illustratethe previously described issue associated with the free play between thesecuring member 4400 and attachment portion 4440. As shown in FIG. 44C,the attachment portion 4440 is disposed within the slot 4412, but one ormore gaps 2880 (individual gaps identified as 4480 a-c) exist betweenthe attachment portion 4440 and corresponding adjacent surfaces of theslot 4412. As such, rotation of the attachment portion 4440, e.g., in afirst direction (R₁) causes the attachment portion 4440 to rotaterelative to the slot 4412, and thus relative to the securing member4400. That is, the initial rotation of the attachment portion 4440, asindicated by (01), is not translated to the securing member 4400 and/orthe corresponding tooth of the patient. Such a translation issue mayoccur (e.g., simultaneously occur) in one or more directions (e.g., themesial, distal, occlusal, gingival, buccal, and/or lingual directions)and/or about one or more axes (e.g., the mesiodistal axis,occlusogingival axis, and/or buccolingual axis). For example, free playbetween the attachment portion and securing member may allow somerotation of an attachment portion relative to the securing member aboutthe mesiodistal axis, the occlusogingival axis, and/or the buccolingualaxis. As a result, such rotation would not be translated to thecorresponding tooth because of the gap between the attachment portionand corresponding securing member. As another example, free play betweenthe attachment portion and securing member may allow some initialmovement of the attachment portion relative to the securing member alongthe mesiodistal axis, the occlusogingival axis, and/or the buccolingualaxis. As a result, such movement would not be translated to thecorresponding tooth because of the gap between the attachment portionand corresponding securing member.

FIG. 45A is a perspective view of another securing member 4500configured in accordance with embodiments of the present technology, andis another example of the above-described concepts regarding free playbetween an arm of an appliance and a securing member. As shown in FIG.45A, the securing member 4500 includes (i) a body region 2905 having afirst, back side or surface to be attached to a patient's tooth and asecond, opposing side or surface, and (ii) one or more coupling arms4510 attached to the second side of the body region 2905. Each couplingarm 4510 can include a first, elongate portion 4512 fixed to the bodyregion 2905, and a second, coupling portion 4514 extending from thefirst portion 4512 and that is partially spaced apart from the bodyregion 2905. The coupling portion 4514 can define a slot or opening 4515configured to receive and partially surround a portion of an orthodonticappliance or arm (as shown in FIG. 45B). In some embodiments, thesecuring member 4500 may be a commercially-available 2D® Lingual Bracketmanufactured by Bernhard Foerster GmbH.

FIG. 45B is a perspective view of a portion of an arm 4530 of anorthodontic appliance coupled to the securing member 4500 shown in FIG.45A. As shown in FIG. 45B, the arm 4530 includes an attachment portionor end portion 4540 having a region or extension 4565 disposed withinthe slot 4515. As also shown in FIG. 45B, when the arm 4530 and securingmember 4500 are installed within a patient's mouth, the x-axis maygenerally correspond to the buccolingual axis, the y-axis may generallycorrespond to the occlusogingival axis, and the z-axis may generallycorrespond to the mesiodistal axis.

FIG. 45C is an enlarged side view of the securing member 4500 andportion of the attachment portion 4540 shown in FIG. 45B, and is meantto further illustrate the previously described issue associated with thefree play between the securing member 4500 and arm 4530. As shown inFIG. 45C, the region 4565 of the attachment portion 4540 is disposedadjacent the securing member 4500 such that one or more gaps 2980(individual gaps identified as 4580 a, 4580 b, 4580 c) exist between theregion 4565 and corresponding adjacent surfaces of the coupling arm 4510of the securing member 4500. As such, free play between the attachmentportion 4540 and securing member 4500 may allow some movement of theregion 4565 relative to the coupling arm 4510 along the mesiodistalaxis, the occlusogingival axis, and/or the buccolingual axis. Forexample, as shown in FIG. 45C, free play between the attachment portion4540 and securing member 4500 may allow movement of the region 4565relative to the coupling arm 4510 by a distance (D₁) along the y-axisand/or a distance (D2) along the x-axis. As a result, such movementwould not be translated to the corresponding tooth because of the one ormore gaps 2980. As another example, rotation of the region 4565 in afirst direction (R₁) can cause the region 4565 to rotate relative to thecoupling arm 4510, and thus the securing member 4500. That is, theinitial rotation of the region 4565 may not be translated to thesecuring member 4500 and/or the corresponding tooth of the patient. Sucha translation issue may occur (e.g., simultaneously occur) in one ormore directions (e.g., the mesial, distal, occlusal, gingival, buccal,and/or lingual directions) and/or about one or more axes (e.g., themesiodistal axis, occlusogingival axis, and/or buccolingual axis). Forexample, free play between the attachment portion 4540 and securingmember 4500 may allow some rotation of the attachment portion 4540relative to the securing member 4500 about the mesiodistal axis, theocclusogingival axis, and/or the buccolingual axis. As a result, suchrotation would not be translated to the corresponding tooth because ofthe gap between the attachment portion 4540 and corresponding securingmember 4500.

Embodiments of the present technology can mitigate this issue (asdescribed with reference to FIGS. 28A-29C) associated with free playbetween the attachment portion and securing member by considering freeplay when designing the orthodontic device. FIG. 46 is a flow diagram ofa method 4600 for generating design parameters and/or manufacturing anorthodontic appliance or related fixture, in accordance with embodimentsof the present technology. The method 4600 includes obtaining datacorresponding to an OTA of a patient (process portion 4602), andobtaining data corresponding to a first FTA of the patient (processportion 4604). As described elsewhere herein, the OTA can be based on ascan of the patient's teeth, and the FTA can be determined and/orprovided by the operator based on the OTA and a desired optimalpositioning of the teeth.

The method 4600 can further include determining data corresponding to asecond FTA (different than the first FTA), based in part on an expectedfree play between an attachment portion of an appliance and acorresponding securing member (process portion 4606). In someembodiments, the expected free play may be a predetermined parameter(e.g., based on the attachment portion and securing member used), inthat the expected free play is known or can be determined prior tomanufacturing of the appliance. In some embodiments, the expected freeplay may correspond to a dimension or angle that causes the design(e.g., shape, thickness, type of spring, etc.) of the appliance orportions thereof (e.g., the arms, biasing portions, attachment portions,etc.) to be modified. For example, if the expected free play between anattachment portion and securing member is 15° in a first direction(e.g., a direction about the mesiodistal axis, occlusogingival axis,and/or buccolingual axis) and the total rotation in the first directionrequired for a particular tooth (e.g., from the OTA to the first FTA) is45°, then the arm (e.g., the attachment portion) of the appliance may bedesigned to rotate 60° in the first direction. In doing so, the arm orattachment portion, when coupled to the corresponding tooth via thecorresponding securing member, will rotate 15° relative to thecorresponding securing member, and then will rotate 45° along with thecorresponding securing member and corresponding tooth, as desired. Aspreviously described, the free play may be adjusted in multipledirections and/or about multiple axes simultaneously for an individualarm. Additionally or alternatively, the free play for each arm of theappliance may be uniquely adjusted relative to the other arms.

In some embodiments, the method 4600 may omit process portion 4606 andonly include a single FTA that considers the expected free play. In suchembodiments, the method 4600 may include receiving first datacorresponding to an OTA of a patient, and providing second datacorresponding to an FTA of the patient, where the second data is basedat least in part on the expected free play between an attachment portionof an appliance and a corresponding securing member or portion thereof.

In some embodiments, the method 4600 can further comprise manufacturingthe fixture and/or the appliance according to at least the datacorresponding to the second FTA. Such manufacturing of the fixtureand/or the appliance can correspond to the manufacturing processesdescribed elsewhere herein.

D. Accounting for Material Properties of the Appliance

Appliances of the present technology are configured to move a patient'steeth from the OTA along a path to a determined and optimal FTA. Aspreviously described, an appliance may be manufactured to have aconfiguration that in its unloaded or unstressed state generallycorresponds to the FTA of the patient's teeth. The appliance isimplanted within a patient's mouth and individual arms of the applianceare coupled to corresponding securing members adhered to the patient'steeth. As the individual arms are coupled to the corresponding securingmember on the patient's teeth in the OTA, the appliance assumes a loadedor stressed configuration. In this loaded configuration, the applianceis often in its most stressed state and thus is most likely, if at all,to experience plastic deformation. If plastic deformation occurs, theindividual arm may not transition from the OTA to the FTA along thedesired path and/or may be unable to provide the necessary force uponthe corresponding tooth. More generally, plastic deformation will limittreatment efficacy of the patient's teeth and prevent or inhibit theteeth from reaching the FTA.

Embodiments of the present technology can mitigate these issues byconsidering plastic deformation, or more particularly avoiding plasticdeformation, when designing the orthodontic appliance and/or fixture. Aspreviously described, embodiments of the present technology maydetermine the path of a patient's teeth from the OTA to the FTA. Assuch, the path of the appliance from a first configuration generallycorresponding to the OTA to a second configuration generallycorresponding to the FTA is also known. Based on the expected path ofthe individual arms of the appliance and the material(s) used to formthe appliance (e.g., the arms, biasing portions, attachment portion,etc.), embodiments of the present technology can determine, and ifnecessary avoid, the appliance's yield strength at which plasticdeformation occurs for each arm. For example, embodiments of the presenttechnology may be able to simulate the stress to be experienced byindividual arms of an appliance when in the first configurationgenerally corresponding to the OTA, or any other configuration betweenthe OTA and FTA. If the stress experienced by one of the arms in anysuch a configuration is expected to be above the yield strength for thematerial of the arm, embodiments of the present technology may thenadjust one or more parameters of the arm such that the yield strength isnot exceeded. In some embodiments, altering one or more parameters ofthe arm can include altering the shape, configuration, and/or dimension(e.g., length, width, and/or thickness) of any portion of the appliance(e.g., the anchor, arms, and/or biasing portions). Altering one or moreof these parameters can increase the yield strength of the arm to begreater than the highest stress expected to be experienced. As but oneexample, certain biasing portions (e.g., spring designs) can experiencea greater stress than other biasing portions. Accordingly, if movementof an arm from the OTA to the FTA is determined to cause the yieldstrength of the arm to be exceeded, embodiments of the presenttechnology may alter the biasing portion of the arm to increase itsyield strength and thereby avoid plastic deformation.

Additionally or alternatively to altering a portion of the appliance inresponse to determining that a yield strength may be exceeded,embodiments of the present technology may alter the path of a patient'stooth from the OTA such that the yield strength of the appliance is notexceeded along the path. That is, if moving a patient's tooth from anOTA to an FTA along a first path will result in yield strength beingexceeded, embodiments of the present technology may instead alter theappliance, or more particularly the corresponding arm of the appliance,such that the patient's tooth is moved from the OTA to the FTA along asecond path, different than the first path, which will result in theyield strength not being exceeded.

FIG. 47 is a flow diagram of a method 4700 for generating designparameters and/or manufacturing an orthodontic appliance or relatedfixture, in accordance with embodiments of the present technology. Themethod 4700 includes obtaining data corresponding to an OTA of a patient(process portion 4702), and obtaining data corresponding to an FTA ofthe patient (process portion 4704). As described elsewhere herein, theOTA can be based on a scan of the patient's teeth, and the FTA can bedetermined and/or provided by the operator based on the OTA and adesired positioning of the teeth.

The method 4700 can further include determining whether an appliance isexpected to exceed a predetermined threshold associated with yieldstrength (process portion 4706). In some embodiments, process portion4706 can include determining whether an appliance configured totransition from a first configuration (e.g., corresponding to the OTA)toward a second configuration (e.g., corresponding to the FTA) isexpected to exceed a yield strength of the appliance. Additionally oralternatively, determining whether the appliance is expected to exceedthe yield strength can include determining whether any portion of theappliance (e.g., individual arms, biasing portions, attachment portions,etc.) is expected to exceed the yield strength. As such, embodiments ofthe present technology may determine the stress experienced by theappliance or any portion thereof when in the first configuration (e.g.,at the OTA), the second configuration (e.g., at the FTA), and/or aplurality of discrete points along the path between the first and secondconfigurations (e.g., at intermediate tooth arrangements (ITA)).

In some embodiments, determining whether the appliance is expected toexceed the yield strength can be based on hysteresis behavior, e.g., ofthe material(s) forming the appliance. With regard to the presenttechnology, hysteresis can alter the path taken by an arm of theappliance depending on whether the arm is experiencing compression ortension along its path from the OTA to the FTA. For example, an armcomprising Nitinol or nickel-titanium alloy may follow a differentstress-strain curve in compression than the arm would in tension.Accordingly, in addition to or in lieu of the determining the expectedstress of the appliance or any portion thereof at discrete pointsbetween and including the OTA and FTA, embodiments of the presenttechnology may consider the configuration of the appliance or anyportion thereof prior to the appliance assuming these discrete points.

In some embodiments, the method 4700 can include, if the appliance isexpected to exceed the predetermined threshold, modifying the appliancesuch that the yield strength is not exceeded (process portion 4708).Modifying the appliance in such a manner can include altering (i) theshape, configuration, and/or dimension (e.g., length, width, and/orthickness) of the appliance (e.g., the anchor, arms, and/or biasingportions), and/or (ii) the material of the arm. Altering one or more ofthese parameters can increase the yield strength of the arm to begreater than the highest stress expected to be experienced, therebyensuring the appliance (or any portion thereof) is not plasticallydeformed in a manner that limits treatment efficacy of the patient'steeth. As an example, if it is determined that an appliance would exceeda predetermined threshold, a single biasing portion (e.g., spring) ofthe appliance could be replaced with two or more lower load biasingportions. Such a replacement may be performed for each arm of theappliance that is expected to exceed the predetermined threshold.

In some embodiments, the method 4700 can further comprise manufacturingthe fixture and/or the appliance. Such manufacturing of the fixtureand/or the appliance can correspond to the manufacturing processesdescribed elsewhere herein.

E. Accounting for Manufacturing Irregularities

As previously described, the 3D configuration of the orthodonticappliance can be created by bending a substantially planar configurationof the appliance to assume the 3D configuration that generallycorresponds to the FTA. In some embodiments, as described elsewhereherein, this bending is accomplished by attaching (e.g., via ligaturewire) a substantially planar configuration of the appliance to a shapeforming fixture that generally corresponds to the FTA (potentially withslight modifications, as previously described), and then heat treatingthe substantially planar configuration such that the appliance assumesand remains in the 3D configuration after heat treatment. In someembodiments, the appliance is made at least in part from a superelasticmaterial (e.g., Nitinol). In such embodiments, the heat treatmentprocess previously described may be relatively mild to ensure thesuperelastic material after heat treatment substantially maintains itselastic properties. However, as a result of such mild heat treatment,the appliance in the 3D configuration or portions thereof can tend toretract partially back toward the previous substantially planarconfiguration after the heat treatment process is complete and theappliance is detached from the fixture. For example, individual arms ofthe appliance in the 3D configuration may move in a direction (e.g., alabial, buccal, gingival, occlusal, mesial, and/or distal direction) orabout an axis (e.g., a mesiodistal axis, occlusogingival axis, and/orbuccolingual axis) after the appliance is detached from the fixtureafter heat treatment. As a result, the heat treated 3D configuration ofthe appliance may not precisely correspond to the shape of the fixture,or more generally, the FTA. Such a discrepancy may cause individual armsof the appliance to apply a force (e.g., a direction and/or magnitude)different than the intended force and thus prevent the patient's teethfrom reaching the desired FTA.

FIG. 48 is a side perspective view of an orthodontic appliance 4800 inaccordance with embodiments of the present technology, and is meant tofurther illustrate the issue regarding an appliance retracting afterheat treatment. For illustrative purposes, only a single arm 4830 of theappliance 4800 is shown, but a person of ordinary skill in the art willappreciate that the principles described herein can apply to any arm4830 of the appliance (e.g., the appliance 100 shown in FIG. 16). Asshown in FIG. 48, the arm 4830 extends along an axis (AFTA), whichcorresponds to the FTA of the patient's teeth. As previously described,due at least in part to the material of the appliance, when theappliance is heat treated over the fixture and detached therefrom, theappliance tends to retract to a previous position other than that of theFTA. As shown in FIG. 48, axis (AR) corresponds to the arrangement theappliance would have after retracting, e.g., from the axis (AFTA). Thatis, if the fixture was heat set while the arm 4830 was positioned alongaxis AFTA, the arm 4830 of the resulting appliance after retractionwould be positioned along axis (AR), which is deflected away from theaxis (AFTA) in which it was heat set and/or toward a more planarconfiguration. Such an arm, or appliance generally, would be spacedapart from the axis (AFTA) and thus, when coupled to a securing memberadhered to a patient's tooth, would provide a force different than thatintended and thus prevent the patient's teeth from reaching the FTA.

Embodiments of the present technology can mitigate this issue byconsidering the material properties of the appliance and irregularitiesassociated with heat treatment, or more generally the manufacturingprocess, when designing the orthodontic appliance and/or fixture. Forexample, embodiments of the present technology may designand/manufacture an appliance to have a configuration that retracts afterheat treatment to have a configuration generally corresponding to theFTA. As shown in FIG. 48, axis (AF) corresponds to the arrangement ofthe fixture and/or the appliance after heat treatment and before theappliance is detached from the fixture. After heat treatment and afterbeing detached from the fixture, the arm 4830 of the appliance 4800 maygenerally retract from the axis (AF) to the axis (AFTA), whichcorresponds to the FTA of the patient's teeth. Accordingly, the axis(AF) can correspond to a position that enables the arm 4830 of theappliance 4800 to have an arrangement corresponding to the FTA for thecorresponding tooth after the appliance has been heat treated, whilealso maintaining the desirable elastic properties of the material, e.g.,to reposition the patient's teeth to the FTA. Stated differently, if afixture is designed to have an arrangement corresponding to the axis(AF), the resulting appliance formed via the fixture after the expectedretraction can have an arrangement corresponding to or positioned alongthe axis (AFTA). In some embodiments, the amount of retraction from theaxis (AF) to the axis (AFTA) may be the same or different than theamount of retraction from the axis (AFTA) to the axis (AR). Accordingly,this varying amount of retraction can be considered during themanufacturing process, e.g., when designing the fixture.

FIG. 49 is a flow diagram of a method 4900 for generating designparameters and/or manufacturing an orthodontic appliance or relatedfixture, in accordance with embodiments of the present technology. Themethod 4900 includes obtaining data corresponding to an OTA of a patient(process portion 4902), and obtaining data corresponding to a first FTAof the patient (process portion 4904). As described elsewhere herein,the OTA can be based on a scan of the patient's teeth, and the FTA canbe determined and/or provided by the operator based on the OTA and adesired positioning of the teeth.

The method 4900 can further include determining data corresponding to asecond FTA (different than the first FTA), based on an expectedvariation of an orthodontic device associated with manufacturing thedevice (process portion 4906). The expected variation can correspond tothe expected different position or arrangement of the retractedappliance after heat treatment (as previously described) relative to theposition or arrangement of the FTA. For example, if the position of aparticular arm of the retracted appliance is spaced apart (e.g., in alingual, occlusal, and/or distal direction) from the position of thecorresponding arm in the FTA, then the expected variation, and thereinthe data corresponding to the second FTA, may correspond to thepositional difference between the arm in the retracted position and thearm in the second FTA position. The expected variation may be apredetermined parameter, in that the expected variation is known or canbe determined prior to manufacturing of the appliance. In someembodiments, the expected variation may be based on one or more factorsincluding (i) the shape, configuration, and/or dimension (e.g., length,width, and/or thickness) of the appliance (e.g., the anchor, arms,and/or biasing portions), (ii) the material(s) of the appliance, (iii)the type of heat treatment applied or expected to be applied (e.g.,maximum temperature of the heat treatment, elapsed time of heattreatment, etc.), and/or (iv) other aspects of the particular patient'sdentition. In some embodiments, the expected variation may be unique toeach arm of the appliance. As such, the expected variation maycorrespond to different values or modifications made to each arm (e.g.,each biasing portion, attachment portion, etc.).

In some embodiments, the method 4900 may omit process portion 4906 andonly include a single FTA that considers the expected variation of theappliance. In such embodiments, the method 4900 may include receivingfirst data corresponding to an OTA of a patient, and providing seconddata corresponding to an FTA of the patient, where the second data isbased in part on the expected variation of the appliance or fixtureassociated with manufacturing, as described above.

In some embodiments, the method 4900 can further comprise manufacturingthe fixture and/or the appliance according to at least the datacorresponding to the second FTA. Such manufacturing of the fixtureand/or the appliance can correspond to the manufacturing processesdescribed elsewhere herein.

F. Accounting for Expected Teeth Movement After Repositioning

Appliances of the present technology are configured to reposition apatient's teeth from the OTA along a path to a determined and optimalFTA. After reaching the FTA, a patient's teeth may experienceorthodontic relapse and move toward their previous position (e.g., theOTA) and thus away from their optimal position. For example, thepatient's teeth may generally move in a partial buccal direction and/ora partial occlusal direction after the teeth are repositioned via theappliance to the FTA. As such, the patient's teeth after relapse may nolonger resemble the FTA. Retainers or other devices may be used toprevent such relapse, however for multiple reasons (e.g., lack ofpatient compliance) these devices are often ineffective.

Embodiments of the present technology can mitigate these issues byconsidering orthodontic relapse when designing the orthodontic applianceand/or fixture. As previously described, the 3D configuration of theorthodontic appliance can be created by bending a substantially planarconfiguration of the appliance to assume a 3D configuration thatgenerally corresponds to the FTA. In some embodiments, this bending isaccomplished by attaching a substantially planar configuration of theappliance to a fixture that generally corresponds to the FTA (withslight modifications, as previously described), and then heat treatingthe substantially planar configuration such that the appliance assumesand remains in the 3D configuration. In order to account for orthodonticrelapse after repositioning a patient's teeth to the FTA, embodiments ofthe present technology can determine the amount of relapse expected tooccur, and alter the design of the appliance and/or fixture accordingly.

FIG. 50 is a flow diagram of a method 5000 for generating designparameters and/or manufacturing an orthodontic appliance or relatedfixture, in accordance with embodiments of the present technology. Themethod 5000 includes obtaining data corresponding to an OTA of a patient(process portion 5002), and obtaining data corresponding to a first FTAof the patient (process portion 5004). As described elsewhere herein,the OTA can be based on a scan of the patient's teeth, and the FTA canbe determined and/or provided by the operator based on the OTA and adesired optimal positioning of the teeth.

The method 5000 can further include determining data corresponding to asecond FTA (different than the first FTA), based in part on an expectedrelapse of the patient's teeth after repositioning, e.g., to the firstFTA and/or second FTA (process portion 5006). The second FTA maycorrespond to a tooth arrangement wherein the expected relapse causesthe patient's teeth to transition from the second FTA to the first FTA,which is the optimal tooth arrangement for the patient. As a result, insome embodiments an appliance having a configuration generallycorresponding to the second FTA may have individual arms with positionsthat are spaced apart in a particular direction (e.g., a labial, buccal,gingival, occlusal, mesial, and/or distal direction) and/or about aparticular axis (e.g., a mesiodistal, occlusogingival, and/orbuccolingual) from the positions of corresponding individual arms of anappliance having a configuration generally corresponding to the firstFTA.

In some embodiments, the expected relapse may be a predeterminedparameter, in that the expected relapse is known or can be determinedprior to manufacturing the appliance and/or fixture. Determining theexpected relapse can be based on the second FTA, the first FTA, the OTA,and/or other factors specific to the patient's dentition. Additionallyor alternatively, the expected relapse may differ for each individualtooth. For example, smaller teeth (e.g., incisors) may experience morerelapse than larger teeth (e.g., molars). As such, individual portionsof the appliance (e.g., the anchor, arms, biasing portions, attachmentportions, etc.) and/or the fixture corresponding to individual teeth maybe adjusted differently and distinctly based on the expected relapse forthat particular portion. For example, modifications made to the smallerteeth, which are expected to experience more relapse, may be smallerthan those made to the larger teeth, which are expected to experienceless relapse.

In some embodiments, the method 5000 may omit process portion 5006 andonly include a single FTA that considers the expected relapse of theappliance. In such embodiments, the method 5000 may include receivingfirst data corresponding to an OTA of a patient, and providing seconddata corresponding to an FTA of the patient, where the second data isbased in part on the expected relapse of the patient's teeth afterrepositioning.

In some embodiments, the method 5000 can further comprise manufacturingthe fixture and/or the appliance according to at least the datacorresponding to the second FTA. Such manufacturing of the fixtureand/or the appliance can correspond to the manufacturing processesdescribed elsewhere herein.

Any of the processes detailed herein can be used with any of the otherprocesses detailed herein. For example, any of the processes describedwith respect to FIGS. 19-25 can be used with any of the processesdescribed with respect to FIGS. 26-34.

As previously noted, an overcorrection process can comprise modifying adesign parameter of an appliance configured to move the tooth, a designparameter of a heat treatment fixture configured for use when setting ashape of an appliance, and/or a final position of one or more of thepatient's teeth. For example, a position of a securing portion of ashape forming fixture can be modified such that, after the appliance iscoupled to the shape forming fixture and heat treated, a position of anattachment portion of the appliance and the position to which theattachment portion moves the tooth are modified.

In any of the embodiments disclosed herein, overcorrection can occurabout one or more specific points on or around a tooth. FIG. 51 depictsan example of how selection of the point(s) about which overcorrectionis applied influences the design parameters of the appliance and/orshape forming fixture and/or the final position of the tooth. FIG. 51depicts a transverse view of a tooth with a bracket bonded to thesurface of the tooth. FIG. 51 depicts the position of the bracketrelative to the tooth when the tooth is in an original position (bracket5100 a), when the tooth is in a preliminary final position (bracket 5100b), when overcorrection has been applied about the center of rotationCoR of the tooth (bracket 5100 c), and when overcorrection has beenapplied at a point on the bracket (bracket 5100 d). As shown in FIG. 51,the bracket will move along a straight line from the original positionto the final position. Additionally, as shown in FIG. 51, the tooth isconfigured to be rotated from about its center of rotation by a firstrotation R1 from the original position to the preliminary finalposition. In some embodiments, it may be advantageous to applyovercorrection to rotate the tooth to a greater extent than the firstrotation R1. It may be advantageous to rotate the tooth according to thesecond rotation R2 based on a predicted relapse of the tooth, forexample. In some embodiments, overcorrection is applied by rotating thetooth about its center of rotation CoR by a second rotation R2 that islarger than the first rotation R1. However, movement of the tooth isaccomplished by an appliance imparting force to the tooth via aconnection between the appliance and the bracket. Such connection pointis not located at the center of resistance CoR of the tooth. Thus, itmay be advantageous to instead apply a rotation and a translation to theposition of the attachment portion of the appliance such that the toothis rotated according to R2.

VII. Communicating the Treatment Plan

In some embodiments of the present technology an orthodontic treatmentplan can be communicated to a clinician such as, but not limited to, anorthodontist, a dentist, or a surgeon. As previously noted,identification of the component tooth movements and suggestions includedin the orthodontic treatment plan can facilitation coordination of theorthodontic treatment, management of patient expectations, etc. Anorthodontic treatment plan and/or information related to the orthodontictreatment plan (e.g., the first data, the second data, the third data,the common movements, the intraarch movements, the suggestions, etc.)can be communicated visually, in writing, audibly, or via any othersuitable form of communication. In some embodiments, orthodontictreatment plan and/or information related to the orthodontic treatmentplan can be communicated via a software platform. For example, FIGS.52A-52C show an animation in a software platform that visuallycommunicates the original, intermediate, and final positions of apatient's teeth (see FIG. 52A, FIG. 52B, and FIG. 52C, respectively). Insome embodiments, the software platform can be configured to visuallydisplay first movements from the original positions to the intermediatepositions (e.g., the intraarch movements) and/or second movements fromthe intermediate positions to the final positions (e.g., commonmovements). In the example animation shown in FIGS. 52A-52C, a patient'steeth 5202 are shown in an original arrangement (see FIG. 52A), anintermediate arrangement (see FIG. 52B), and a final arrangement (seeFIG. 52C). The animation can include one or more indicators 5204configured to communicate useful information regarding the arrangementof the teeth 5202 and/or movements of the teeth to an operator. In theexample shown in FIGS. 52A-52C, the indicator 5204 can comprise a firstbar 5206 representing a magnitude and/or a duration of one or more typesof tooth movements and/or a second bar 5208 representing a magnitudeand/or a duration of one or more other types of tooth movements. Forexample, the first bar 5206 can represent the blue movements of atreatment plan and the second bar 5208 can represent the orange and/orpurple movements of the treatment plan. In these embodiments and others,the indicators 5204 can include a symbol, character, or other indiciaconfigured to communicate to an operator the portion of the movementsrepresented by the first and second bars 5206, 5208 that the teeth 5202have been moved by in the arrangement the teeth 5202 are depicted in.

In some embodiments, an orthodontic treatment plan and/or a portionthereof can be communicated to a human operator during any portion ofthe processes disclosed herein. Communicating the treatment plan canfacilitate obtaining the treatment plan and/or modifying the treatmentplan such that the treatment plan is achievable and/or realistic. Insome cases, the human operator can be an aligning technician responsiblefor obtaining the second data characterizing the final positions of thepatient's teeth based on the original positions and instructions from aclinician. In some cases, the human operator can be a clinicianresponsible for coordinating the orthodontic treatment. For example, ananimation in a software platform, such as the animation described abovewith respect to FIGS. 52A-52C, can visually communicate an angulardisplacement between a patient's mandible and maxilla about one or bothcondyloid processes of the patient's mandible when the patient's teethare in an original arrangement, a final arrangement, an intermediatearrangement, etc. Communication of the angular displacement(s) canindicate to the operator if there is excessive contact and/or excessivespacing between the patient's teeth. This information can becommunicated to the operator such that the operator can approve theorthodontic treatment plan or modify the orthodontic treatment plan(e.g., the final positions of the teeth, the suggested orthodonticinterventions, etc.). For example, based on the angular displacement,the operator could determine that a bite plate or splint should be usedduring surgical intervention or use of an appliance to address, forexample, temporomandibular joint issues related to the angulardisplacement(s).

VIII. Evaluating an Orthodontic Treatment

It can be advantageous to evaluate an orthodontic treatment duringand/or after implementation of the treatment to assess the progress ofthe treatment. If a patient's teeth have not moved as planned, thetreatment may need to be modified and/or further treatment may berequired to accomplish the objectives of the orthodontic treatment(e.g., proper occlusion, improved aesthetics, etc.). For example, if apatient's teeth are moving slower than anticipated in response toinstallation of an appliance, the pace of movement may be indicative ofthe appliance imparting insufficient forces to the teeth to move theteeth to their final positions. In cases in which an orthodontictreatment is not progressing as planned, secondary orthodonticinterventions (e.g., additional appliances, new appliances, differenttypes of interventions, etc.) may be required to reposition thepatient's teeth to the final positions. It may be beneficial to modifysuch secondary interventions based on an evaluation of the firstintervention. As an example, if rotation of one of a patient's lateralincisors occurred very slowly or to a very small degree, a secondaryappliance can be designed to apply larger forces to the lateral incisorto rotate the tooth to a greater degree and/or faster.

Traditionally, evaluation of orthodontic treatment is performed by ahuman operator (e.g., a clinician, the patient, etc.). An orthodontistcan visually inspect a patient's teeth and, using their clinicaltraining and experience, assess how the teeth are moving (e.g., whetherthe teeth are moving in the desired directions, whether the teeth aremoving at a desirable pace, etc.) and determine whether modifications tothe treatment and/or further treatment are needed to accomplish thetreatment objectives. However, such clinical evaluation is qualitativeand relies heavily on the skill of the human operator, and it can bechallenging to accurately and precisely identify the magnitude,direction, and pace of movements of the teeth that have occurred andresidual movements of the teeth that should be accomplished for theteeth to reach their planned positions. To address these challenges,methods of evaluating orthodontic treatment in accordance with thepresent technology employ quantitative, numerical processes foridentifying current, actual positions of the patient's teeth duringand/or after an orthodontic treatment, the actual movements of the teeththat have occurred during the orthodontic treatment, and the residualmovements required for the teeth to reach planned, final positions. Invarious embodiments, a method of evaluating an orthodontic treatmentcomprises obtaining one or more performance parameters of the treatment(e.g., accuracy, efficiency, etc.), which can be used to determinewhether to modify the current treatment, if the treatment is completedor if further treatment is needed and how to proceed with treatment.Additionally or alternatively, aggregation and analysis of the datadisclosed herein (e.g., position data, movement data, performanceparameter data, etc.) can be used to inform and improve futureorthodontic treatments.

FIG. 53 is a flow chart of an example process 5300 for evaluating anorthodontic treatment in accordance with the present technology. Atprocess portion 5302, the process 5300 can comprise obtaining originalposition data characterizing original positions of a patient's teeth(e.g., when the teeth are in the OTA, prior to implementation of theorthodontic treatment, etc.), planned position data characterizingplanned positions of the patient's teeth (e.g., planned final positions,planned intermediate positions, etc.), and/or planned movement datacharacterizing planned movements of the patient's teeth from theoriginal positions to the planned positions. At process portion 5304,the process 5300 can comprise obtaining actual position datacharacterizing the patient's anatomy (e.g., teeth, gingiva, skull, etc.)in an actual tooth arrangement (ATA) during and/or after the orthodontictreatment. The process 5300 can also include obtaining actual movementdata characterizing actual movements of the patient's teeth from theoriginal positions to the positions of the teeth in the ATA (e.g.,actual positions) and/or residual movement data characterizing residualmovements of the patient's teeth from the actual positions to theplanned positions. The process 5300 can continue at process portion 5306with comparing the planned and actual position data, comparing theplanned and actual movement data, and/or evaluating the residualmovement data. Such comparisons and evaluations can be used to determinewhether objectives of the orthodontic treatment have been and/or areprojected to be accomplished, which can be used to determine whether thetreatment should be completed, modified, or extended and/or if and how asecondary treatment should be implemented.

The original position data can characterize original positions of thepatient's teeth (e.g., positions of the patient's teeth prior toimplementation of some or all of an orthodontic treatment). The originalposition data can be similar to the OTA data and/or the OTA digitalmodel, as described herein. The original position data can comprise adataset defining 3D coordinates of one or more portions of the patient'sanatomy (e.g., teeth, gingiva, jaw bone, skull, etc.). For example, theoriginal position data can comprise a point cloud defining 3Dcoordinates of a plurality of points characterizing the surfaces of theteeth. Additionally or alternatively, the original position data cancomprise a dataset defining 3D coordinates of a specific reference point(e.g., center of mass, etc.) of one or more of the patient's teeth. Insome embodiments, the original position data comprises a digital modelof the patient's anatomy. The digital model can comprise a continuous,unsegmented digital model of the teeth, gingiva, jaw bone, skull, orother anatomical structures. Additionally or alternatively, the digitalmodel can comprise one or more individual models (e.g., an individualmodel of each tooth, an individual model of the gingiva, an individualmodel of the jaw bone, an individual model of the skull, etc.) producedby segmenting a continuous model of the anatomical structures. As butone example, the original position data can comprise one digital modelrepresenting a patient's skull based on CBCT image data, another digitalmodel representing the patient's maxilla based on CBCT image data, aplurality of other digital models each representing one of the patient'steeth based on intraoral scan data, and/or yet another digital modelrepresenting the patient's gingiva based on intraoral scan data. Suchdigital model(s) can comprise a mesh model (e.g., a triangle mesh model,a polygon mesh model, a volumetric mesh model, etc.), a surface model(e.g., a non-uniform rational basis spline (NURBS) surface model, aT-Spline surface model, etc.), a parametric CAD model, or anothersuitable type of model.

The planned position data can characterize planned positions of thepatient's teeth after the patient's teeth have been moved via some orall of an orthodontic treatment. The planned position data can besimilar to the FTA data, the ITA data, the FTA digital model, and/or theITA digital model, as described herein. The planned position data cancomprise a dataset defining 3D coordinates of one or more portions ofthe patient's teeth and/or gingiva. For example, the planned positiondata can comprise a point cloud defining 3D coordinates of a pluralityof points defining the surfaces of the teeth. Additionally oralternatively, the planned position data can comprise a dataset defining3D coordinates of a reference point (e.g., a center of mass, etc.) ofone or more of the patient's teeth. In some embodiments, the plannedposition data comprises a digital model of the patient's teeth and/orgingiva. The digital model can comprise a continuous, unsegmenteddigital model of the teeth and/or gingiva. Additionally oralternatively, the digital model can comprise one or more individualmodels of a tooth or the gingiva produced by segmenting a continuousmodel of the teeth and/or gingiva. The digital model can comprise a meshmodel (e.g., a triangle mesh model, a polygon mesh model, a volumetricmesh model, etc.), a surface model (e.g., a non-uniform rational basisspline (NURBS) surface model, a T-Spline surface model, etc.), aparametric CAD model, or another suitable type of model.

In some embodiments, the planned movements comprise overall movements ofthe teeth from the original positions to the planned positions. Forexample, as described herein, an overall movement of a tooth can bedefined by a 3D vector characterizing a displacement between a referencepoint of the tooth (e.g., a center of mass of the tooth, a center ofmass of the crown of the tooth, one or more points on a surface of thecrown of the tooth, etc.) in the original position and a correspondingreference point of the tooth in the planned position. In someembodiments, the overall movement can be defined by a 3D transformationcharacterizing a rotation and/or a translation of the tooth as a 3D bodyfrom the original position to the planned position. Additionally oralternatively, the planned movements can comprise one or more componentmovements of the teeth from the original positions to the plannedpositions. For example, the planned movements can comprise a movementthat is unique to each tooth (e.g., a blue movement), a movement that iscommon to all of the teeth in one of the patient's dental arches (e.g.,an orange movement), a movement that is common to all of the teeth inboth of the patient's dental arches (e.g., a purple movement), etc.

As previously noted, at process portion 5304 the process 5300 cancomprise obtaining actual position data, actual movement data, and/orresidual movement data. The actual movement data characterizes actualpositions of the patient's teeth at the time that the actual positiondata is obtained. The actual position data can be obtained at one ormore predetermined times during and/or after the treatment. For example,the actual position data can be obtained at regular intervals during thetreatment such that progress of the treatment can be monitored while thetreatment is ongoing. In some embodiments, the actual position data canbe obtained after a predetermined amount of time has passed such thatthe patient's teeth are expected to be located at their plannedpositions. For example, the actual position data can be obtained afteran estimated duration of the treatment has elapsed to evaluate whetherthe teeth reached their desired, final positions and if furthertreatment is beneficial and/or necessary. Additionally or alternatively,a clinician and/or the patient can determine when the actual positiondata is obtained. For example, a clinician can visually inspect apatient's teeth at an appointment. If the clinician suspects from thevisual inspection that the treatment is not progressing as planned, theclinician can determine that the actual position should be obtained, andthe progress of the treatment should be evaluated.

The actual position data can comprise a dataset defining 3D coordinatesof one or more portions of the patient's teeth and/or gingiva. Forexample, the actual position data can comprise a point cloud defining 3Dcoordinates of a plurality of points defining the surfaces of the teeth.Additionally or alternatively, the actual position data can comprise adataset defining 3D coordinates of a reference point (e.g., a center ofmass, etc.) of one or more of the patient's teeth. In some embodiments,the actual position data comprises a digital model of the patient'steeth and/or gingiva. The digital model can comprise a continuous,unsegmented digital model of the teeth and/or gingiva. Additionally oralternatively, the digital model can comprise one or more individualmodels of a tooth or the gingiva produced by segmenting a continuousmodel of the teeth and/or gingiva. The digital model can comprise a meshmodel (e.g., a triangle mesh model, a polygon mesh model, a volumetricmesh model, etc.), a surface model (e.g., a non-uniform rational basisspline (NURBS) surface model, a T-Spline surface model, etc.), aparametric CAD model, or another suitable type of model.

In some embodiments, the process 5300 includes obtaining actual movementdata and/or residual movement data (e.g., at process portion 5304). Theactual movement data can characterize actual movements of the teeth fromtheir original positions to their actual positions and the residualmovement data can characterize residual movements of the teeth fromtheir actual positions to their planned positions (e.g., movements thathave not yet been accomplished). An actual movement and/or a residualmovement can be defined by a 3D vector characterizing a distance betweencorresponding reference points of a tooth in the actual position and theoriginal position or the planned position, respectively. In someembodiments, the actual movement and/or the residual movement can bedefined by a 3D transformation characterizing a rotation and/or atranslation of the tooth as a 3D body between the actual position andthe original position or the planned position, respectively. The actualmovements and/or the residual movements can each comprise overallmovements and/or one or more component movements.

At process portion 5306, the process 5300 can comprise evaluating theposition data and/or the movement data. For example, the process 5300can comprise comparing the actual positions of the teeth ascharacterized by the actual position data to the planned positions ofthe teeth as characterized by the planned position data to determine ifthe teeth have reached their desired positions. In some embodiments,comparing the actual position data to the planned position datacomprises evaluating the residual movement data. For example, evaluatingthe residual movement data can comprise comparing the residual movementdata to a predetermined threshold to determine if the residual movementscan be accomplished by a specific type of orthodontic intervention.Additionally or alternatively, the process 5300 can comprise comparingthe actual positions of the teeth to the original positions of the teethand/or evaluating the actual movement data. For example, evaluating theactual movement data can comprise comparing the actual movement data tothe planned movement data to determine a percentage of the plannedmovement data that was accomplished. Such evaluation can provide insightinto an accuracy and/or an efficiency of the orthodontic treatment.

FIG. 54 is a flow chart of an example of a process 5400 for obtainingactual position data, actual movement data, and residual movement data(e.g., process portion 5304 of FIG. 53). As shown in FIG. 54, theprocess 5400 can comprise obtaining an ATA digital model of a patient'steeth and gingiva in an actual arrangement at process portion 5402.Obtaining the ATA digital model can be similar to obtaining the OTAdigital model, as described herein. For example, obtaining the ATAdigital model can comprise scanning the patient's oral cavity with anintraoral scanner, imaging the patient's skull, face, and/or jaws withCBCT, etc. In some embodiments, obtaining the ATA digital modelcomprises obtaining a single, continuous digital model of the patient'steeth and/or gingiva. At process portion 5404, the process 5400 cancomprise segmenting the ATA digital model into one or more individualtooth and gingiva models. For example, the ATA digital model can besegmented such that the ATA digital model comprises a plurality ofindividual digital models each representing one of the patient's teethor the patient's gingiva.

To compare the actual positions of the patient's teeth to the plannedand/or original positions of the patient's teeth, as can be an objectiveof evaluating an orthodontic treatment, it can be beneficial and/orpreferable for a shape (e.g., a surface geometry, etc.) of a tooth inthe ATA digital model to be as similar as possible to a shape of thetooth in the OTA or FTA digital model. For example, in some embodimentsa position of a tooth is defined at the center of mass of the tooth.Because the coordinates of a body's center of mass are dependent on ageometry of the body, the center of mass of the tooth will havedifferent coordinates in the ATA digital model and the FTA digital modelif the shape of the tooth in the ATA digital model differs from theshape of the tooth in the FTA digital model. If the actual and plannedpositions of the tooth are evaluated at the center of mass of the toothand the center of mass is different in the ATA and the FTA due to adifference in shape of the tooth, the actual position of the tooth willbe different than the planned position of the tooth, even if the actualand planned positions were equivalent. Because the FTA digital model canbe obtained by moving the teeth of the OTA digital model, in many casesthe teeth in the FTA digital model have the same shape as the teeth inthe OTA digital model. However, because the digital models of the teethin the ATA digital model are obtained from new scan and/or image dataobtained after the OTA data has been obtained, one or more of the teethin the ATA digital model may have a different shape than a shape of acorresponding tooth in the OTA and FTA digital models. For example, anATA digital model produced from an optical scan may have holes orregions where the patient's anatomy was not sufficiently captured by thescanner. If the ATA digital model comprises a mesh model generated byreconstructing surfaces of the teeth from a point cloud or other imagedata, errors in the surface reconstruction may cause the shape of thetooth in the ATA digital model to differ from the shape of the tooth inthe OTA digital model. In some cases, a patient may have undergoneinterproximal reduction (IPR) or other dental procedures (e.g., filings,crowns, etc.) that modified a shape of a tooth between obtaining the OTAdigital model and obtaining the ATA digital model.

To address the above-noted concerns, the process 5400 for obtaining theactual position data can comprise replacing the individual digitalmodels of the teeth in the ATA digital model with individual digitalmodels of the teeth from the OTA digital model or the FTA digital model(process portion 5406). Because the teeth in the FTA digital model canhave the same shape as the teeth in the OTA digital model, either areappropriate to use at process portion 5406. The outcome of processportion 5406 can comprise an ATA digital model comprising individualdigital models of the teeth from the OTA or FTA digital model that areeach located at the actual position of the corresponding tooth. The newATA digital model with the OTA or FTA teeth at the actual positions canthen be compared to the OTA digital model of the teeth in the originalpositions and/or the FTA digital model of the teeth in the plannedpositions because corresponding teeth of each of the models will havethe same shape, just different positions. In some embodiments, ratherthan replacing the individual tooth models of the ATA digital model withindividual tooth models from the OTA or FTA digital model, theindividual tooth models of the OTA or FTA digital model can be replacedwith individual tooth models of the ATA digital model to produce an OTAor FTA digital model comprising individual digital models of the teethfrom the ATA digital model located at the original positions or finalpositions, respectively.

FIGS. 55A-55C illustrate an example of replacing individual teeth models5502 of an ATA digital model 5500 with individual teeth models 5506 ofan OTA digital model 5504 to facilitate understanding of process portion5406. One or more of the individual teeth models 5502 of the ATA digitalmodel 5500 may, in some cases, have one or more holes, artifacts, ordefects such that a shape of the tooth represented by the individualtooth model 5502 of the ATA digital model 5500 differs from a shape ofthe corresponding individual tooth model 5506 of the OTA digital model5506. Additionally or alternatively, one or more of the individual teethmodels 5502 may characterize a true change in shape of the correspondingtooth.

Process portion 5406 can comprise registering the individual teethmodels 5506 in the OTA digital model 5504 to the individual teeth models5502 in the ATA digital model 5500. In some embodiments, theregistration occurs one tooth at a time. For example, a first toothmodel 5506 of the OTA digital model 5504 can be registered to acorresponding first tooth model 5502 of the ATA digital model 5500, asecond tooth model 5506 of the OTA digital model 5504 can be registeredto a corresponding second tooth model 5502 of the ATA digital model5500, etc. In some embodiments, registering one of the OTA individualteeth models 5506 to a corresponding one of the ATA individual teethmodels 5502 comprises transforming the OTA individual tooth model 5506such that a coordinate system of the OTA individual tooth model 5506 isaligned with a coordinate system of the ATA individual tooth model 5502,a feature of the OTA individual tooth model 5506 is aligned with acorresponding feature of the ATA individual tooth model 5502, a distancebetween references points of the OTA individual tooth model 5506 andcorresponding reference points of the ATA individual tooth model 5502 isreduced or minimized, etc. Registering one of the OTA individual teethmodels 5506 to a corresponding one of the ATA individual teeth models5502 can be an iterative process. Once the OTA individual tooth models5506 have been registered with the corresponding ATA individual toothmodels 5502, the ATA individual tooth models 5502 can be deleted suchthat the ATA digital model 5500 comprises the OTA individual toothmodels 5506 located at the actual positions of the teeth.

In some embodiments, it can be advantageous to evaluate the actualpositions at which securing members (e.g., an orthodontic brackets,etc.) were bonded to a patient's teeth in addition to, or in place of,evaluating actual positions of the teeth themselves. The position of asecuring member on a tooth can influence the magnitude and/or directionof a force applied to the tooth by an appliance via the securing member.In various cases, an indirect bonding tray can be used to facilitatebonding of the securing members to the patient's teeth. However, errorsin positioning of the securing members can still occur due to defects inthe bonding tray, clinician inexperience, complex anatomy, and otherreasons. Accordingly, it can be useful to evaluate how accurately thesecuring members were bonded to a patient's teeth which can informdesigns of future orthodontic interventions, clinician training, etc.

In some embodiments, an actual position of a securing member can beobtained after the OTA individual tooth models (or FTA individual toothmodels) have been aligned with corresponding ATA individual toothmodels. As shown in FIGS. 55A-55C, the ATA digital model can be obtainedby scanning and/or imaging a patient's teeth while the securing membersare secured to the teeth such that the ATA digital model characterizesthe securing members. Obtaining an actual position of one of thesecuring members can comprise obtaining 3D coordinates of one or morereference points of the securing member and/or obtaining a rotationmatrix defining an orientation of the securing member, as the securingmember is represented in the ATA digital model. An intended position ofthe securing member can be obtained from a corresponding OTA (or FTA)individual tooth model that is aligned with the ATA individual toothmodel such that the actual and intended positions of the securing memberare comparable. For example, after aligning individual tooth models 5506of the OTA digital model 5504 to the individual tooth models 5502 of theATA digital model 5500 and prior to deleting the individual tooth models5502 of the ATA digital model 5500 (e.g., such that correspondingindividual tooth models 5502, 5506 are aligned) the intended positionsof the securing members can be obtained from the individual tooth models5506 of the OTA digital model 5504 and the actual positions of thesecuring members can be obtained from the individual tooth models 5502of the ATA digital model 5500.

Referring back to FIG. 54, the process 5304 for determining actualposition data can comprise registering the ATA digital model to the FTAdigital model (process portion 5408) and/or to the OTA digital model. Tocompare the actual positions of a patient's teeth obtained from the ATAdigital model to the desired, final positions of the teeth obtained fromthe FTA digital model, the actual positions and final positions shouldbe measured with reference to the same coordinate system. For example,original positions of the patient's teeth obtained from an OTA digitalmodel and the final positions of the patient's teeth obtained from theFTA digital model may be comparable because the FTA digital model isderived from the OTA digital model and shares the same coordinate systemas the OTA digital model. However, because the ATA digital model can begenerated independently of the OTA and FTA digital models, the ATAdigital model may have a unique coordinate system. Accordingly, methodsof the present technology are directed to processes for registering onedigital model to another digital model such that the digital modelsshare a common coordinate system.

FIGS. 56A and 56B illustrate an example of such registration and areprovided as visual aids to facilitate the discussion of process portion5408. Specifically, FIGS. 56A and 56B depict a digital environment 5600with an FTA digital model 5602 and an ATA digital model 5604 positionedin the digital environment 5600. As shown in FIG. 56A, the digitalenvironment 5600 can comprise an environment coordinate system 5606. Anyof the coordinate systems disclosed herein, including the environmentcoordinate system 5606, can comprise a Cartesian coordinate system withthree orthogonal axes and an origin (as shown in FIG. 56A), acylindrical coordinate system, a spherical coordinate system, etc. TheFTA digital model 5602 comprises an FTA coordinate system 5608, whichmay or may not be aligned with the environment coordinate system 5606,and the ATA digital model 5604 comprises an ATA coordinate system 5610,which, as shown in FIG. 56A, in some cases may not be aligned with FTAcoordinate system 5608 and/or the environment coordinate system 5606.For example, as shown in FIG. 56A, the ATA coordinate system 5610 can berotated and/or translated relative to FTA coordinate system 5608. As aresult, a center of mass of a tooth in the ATA digital model 5604 thatis measured with respect to the environment coordinate system 5606 and acenter of mass of a corresponding tooth in the FTA digital model 5602that is measured with respect to the environment coordinate system 5606will be spaced apart by a substantial distance that is not reflective ofthe true distance between the tooth's actual position and the tooth'splanned, final position.

The ATA digital model 5604 can be registered to the FTA digital model5602 such that coordinates of corresponding features, portions, orpoints of the digital models 5604, 5602 are comparable. According tovarious embodiments, registering the ATA digital model 5604 to the FTAdigital model 5602 comprises determining the spatial transformation thataligns the ATA digital model 5604 to the FTA digital model 5602 and/oraligns the ATA coordinate system 5610 to the FTA coordinate system 5608.Additionally or alternatively, the ATA digital model can be registeredto the OTA digital model (not shown). FIG. 56B illustrates an example ofthe FTA digital model 5602 and the ATA digital model 5604 positioned inthe digital environment 5600 after the ATA digital model 5604 has beenregistered to the FTA digital model 5602. A variety of methods can beused to register the ATA digital model 5604 to the FTA digital model5602, which are described in greater detail below.

According to various embodiments, registering the ATA digital model 5604to the FTA digital model 5602 comprises identifying one or morecorrespondences on each of the digital models 5602, 5604 and determiningthe transformation that positions the correspondences relative to oneanother in a specific manner, for example aligning the correspondences.A correspondence can comprise an anatomical landmark (e.g., a crest of atooth, a ridge of a tooth, a gingival edge of a crown of a tooth, aportion of a skull, etc.), a point (e.g., a center of mass of the tooth,a center of mass of the crown of the tooth, a point on a surface of atooth, etc.), a line, a surface, a body, a coordinate system, or anothersuitable geometric reference. As discussed in greater detail below,correspondences of the digital models 5602, 5604 and/or their positionscan be known. Additionally or alternatively, the correspondences may notbe known initially, but can be identified through an iterative process.

In some embodiments, registering the ATA digital model 5604 to the FTAdigital model 5602 comprises identifying one or more correspondences oneach of the digital models 5602, 5604 that is not expected to move overat least a portion of the orthodontic treatment, obtaining the positionsof the correspondences, and determining a difference between thepositions of the correspondences. The difference in positions can serveas the basis for and/or substantially correspond to a transformationthat, when applied to the ATA digital model 5604, minimizes a distancebetween the correspondences. For example, if each of the FTA digitalmodel and the ATA digital model includes a representation of a skull ofa patient (e.g., from CBCT image data), one or more portions of theskull can serve as the correspondence in each of the digital models5602, 5604. Because the shape and position of the skull are not expectedto change during the orthodontic treatment, the position of the skullcorrespondence of the ATA digital model 5604 should be the same as theposition of the skull correspondence of the FTA digital model 5602.Accordingly, a difference in the positions of the correspondences of theATA digital model 5604 and the FTA digital model 5602 can be obtained.The ATA digital model 5604 can be moved according to a transformationcorresponding at least in part to the difference in positions of thecorrespondences to register the ATA digital model 5604 to the FTAdigital model 5602.

Other stationary anatomical features that can be used as knowncorrespondences can include certain soft tissues (e.g., the rugae of thepalate, etc.), certain bones of the head, face, jaws, and/or neck,and/or the teeth. For example, if an overall planned movement of a toothis negligible or nonexistent, the position of the tooth in the ATAdigital model 5604 should be the same as or similar to the position ofthe tooth in the FTA digital model 5602.

However, in some cases all a patient's teeth may have non-negligibleplanned movements. Additionally or alternatively, the digital models5602, 5604 may not include the stationary anatomical features notedabove. For example, CBCT image data might not be obtained for everypatient, and intraoral scan data may only include the teeth and gingiva,which can move during treatment. To address these limitations, a methodof registering the ATA digital model 5604 to the FTA digital model 5602can comprise determining a transformation that can be applied to the ATAdigital model 5604 to reduce or minimize an error between multipleanatomical features (e.g., all of the teeth, some of the teeth, etc.).As an example, such a method can comprise obtaining actual position datacharacterizing a position of one or more points per tooth in the ATAdigital model 5604 and planned position data characterizing a positionof the same one or more points per tooth in the FTA digital model 5602.In some embodiments, the one or more points comprise a center of mass ofthe tooth, a center of mass of the crown, a point on a surface of thetooth, etc. The actual position data can be symbolically transformed todetermine symbolic registered actual position data, and a regressionanalysis can be performed to determine numerical equivalents of thesymbolic transformation and the symbolic registered actual position databased on one or more cost functions (e.g., a loss function, an errorfunction, an objective function, etc.). For example, a transformationcan be identified such that an error parameter characterizing adifference between the registered actual position data and the plannedposition data is minimized. The error parameter can comprise a measureof the distances between corresponding teeth. For example, the errorparameter can comprise a sum of the squared distance between theregistered actual position and the planned position of each tooth,summed over all of the teeth. In some embodiments, registering the ATAdigital model 5604 to the FTA digital model 5602 comprises a processthat is the same as, or similar to, the processes described in referenceto FIGS. 26-32E.

In some embodiments, an optimization-based registration can be performedto register the ATA digital model 5604 to the FTA digital model 5602.For example, the ATA digital model 5604 can be transformed to obtain aregistered ATA digital model 5604, an error parameter can be evaluatedto characterize a difference in position between one or more portions ofthe ATA digital model 5604 and the FTA digital model 5602, and thetransformation and error evaluation can be repeated until the errorfalls within a desirable range or a maximum number of iterations hasbeen reached. In these and other embodiments, the correspondences maynot be known between the ATA digital model 5604 and the FTA digitalmodel 5602. For example, registering the ATA digital model 5604 to theFTA digital model 5602 can comprise an iterative closest point (ICP)algorithm in which an initial set of correspondences is identified. Thecorrespondences can be identified by selecting a number of referencepoints on one of the digital models and identifying the closest point onthe other digital model to each of the reference points A transformationcan be applied to the ATA digital model 5604 to obtain a registered ATAdigital model and an error parameter between the registered ATA digitalmodel and the FTA digital model 5604 can be obtained. The previousprocess portions, including identifying the correspondences, can berepeated one or more times.

In one example, registering the ATA digital model 5604 to the FTAdigital model 5602 comprises aligning the ATA coordinate system 5610 tothe FTA coordinate system 5608. In embodiments in which the ATA and FTAcoordinate systems 5610, 5608 comprise Cartesian coordinate systems withthree orthogonal axes (e.g., as shown in FIGS. 56A and 56B, etc.),aligning the coordinate systems 5608, 5610 can comprise rotating and/ortranslating one of the coordinate systems 5608, 5610 such thatcorresponding axes of the coordinate systems 5608, 5610 extend in thesame direction. In some embodiments, aligning the coordinate systems5608, 5610 comprises positioning an origin of one of the coordinatesystems 5608, 5610 at the same position as an origin of the other of thecoordinate systems 5608, 5610.

Referring back to FIG. 54, once the ATA digital model 5604 has beenaligned to the FTA digital model 5602, the actual positions of the teethin the reference coordinate system can be obtained (process portion5410). In some embodiments, the actual positions are defined by 3Dcoordinates of one or more points for each tooth in the ATA digitalmodel 5604. In some embodiments, the one or more points comprise acenter of mass of the tooth, a point on a surface of the tooth, oranother suitable reference point. Additionally or alternatively, anorientation of the tooth in the ATA digital model 5604 can be defined bya rotation matrix defining angles of rotation of the tooth about theaxes of the reference coordinate system.

At process portion 5412, residual movement data can be obtained bydetermining a residual movement (e.g., a displacement) of one or more ofthe teeth between the actual position of the tooth and the planned,final position of the tooth. In various embodiments, the residualmovement comprises a movement that should preferably be completed forthe objectives of the orthodontic treatment to be achieved (e.g., suchthat the teeth reach their desired, final positions). In someembodiments, a residual movement of a tooth comprises a 3D vectordefining a difference between the 3D coordinates of a reference point ofthe tooth in the actual position and the 3D coordinates of acorresponding reference point of the tooth in the final position.Additionally or alternatively, a residual movement of a tooth cancomprise a transformation matrix defining a translation and a rotationof the tooth between its actual position and its final position. Forexample, the transformation matrix can comprise a 4×4 matrix including a3D rotation matrix and a 3D displacement vector. The transformationdefining the residual movement between the actual and final positions ofthe tooth can be affine, rigid, or nonrigid.

In some embodiments, it can be useful to decompose the overall residualmovements (e.g., displacements between the actual and final positions ofthe teeth) into one or more component movements. As described herein,for example with reference to FIGS. 22A-24C, a component movement caninclude movement of all of a patient's teeth within both of thepatient's dental arches according to the same transformation (e.g., apurple movement), movement of all of a patient's teeth within one of thepatient's dental arches according to the same transformation (e.g., anorange movement), movement of the patient's teeth within one dental archrelative to one another (e.g., a blue movement), etc. If the orthodontictreatment comprises the use of multiple orthodontic interventions toaccomplish different component movements (e.g., elastics to accomplishinterarch movements with an appliance to accomplish intraarch movements,surgery to accomplish purple movements with an appliance to accomplishblue movements, etc.) it can be advantageous to evaluate the degree towhich each individual intervention has accomplished each componentmovement. As one example, if an appliance has accomplished all of theplanned intraarch movements of a treatment plan but the elastics haveonly accomplished half of the planned interarch movements of a treatmentplan, the decisions made with regards to how to proceed with treatmentto accomplish the residual movements that still need to be completed maydiffer drastically from the decisions made with regards to how toproceed with treatment if the elastics have accomplished all of theinterarch movements but the appliance has only accomplished half of theintraarch movement. For example, one or more orthodontic interventionscan be discontinued once the associated component movements to beaccomplished by the intervention have been completed.

Decomposing the overall residual movements can be similar to theprocesses disclosed herein, for example with reference to FIGS. 30-32E,for decomposing overall planned movements. For example, decomposing theoverall residual movements can comprise performing a tooth registrationto obtain a unique movement of each tooth (e.g., a blue movement) and acommon movement of all of the teeth (e.g., an orange movement).Decomposing the overall residual movements comprises determining atransformation that can be applied to the teeth in the ATA digital modeland/or the teeth in the FTA digital model such that an error parameterdefining a difference between the spatial positions of the digitalmodels is reduced or minimized. In some embodiments, the overallresidual movements can be decomposed to determine intermediate positionsof the teeth corresponding to positions of the teeth after the bluemovements have been applied to the teeth in their actual positions. As avisual example of various tooth arrangements after overall and componentmovements, FIG. 57 illustrates a digital environment 5700 comprising adigital model of the patient's teeth in an original arrangement 5702, adigital model of the patient's teeth in a final arrangement 5704, and adigital model of the patient's teeth in an actual arrangement 5706, anda digital model of the patient's teeth in such an intermediatearrangement 5708.

As shown in FIG. 57, moving the patient's teeth from the originalarrangement 5702 to the final arrangement 5704 can comprise moving theteeth according to blue movements (e.g., to improve an alignment of theteeth in one arch) and orange movements (e.g., to improve an occlusionby moving all of the teeth in one arch). In the actual arrangement 5706shown in FIG. 57, neither the blue movements nor the orange movementshave been entirely accomplished. Specifically, the central incisors arenot properly aligned with the other teeth in the dental arch, and all ofthe teeth in the dental arch need to move according to a common, orangemovement to reach the final arrangement 5704. It can be beneficial toevaluate the progress of various types of orthodontic tooth movements,as well as evaluating an overall progress of the treatment. In someembodiments, various types of movements to be accomplished during anorthodontic treatment can occur at varying magnitudes and rates. Forexample, if one type of movement is to be accomplished by an orthodonticintervention whose efficacy is heavily reliant on patient compliance(e.g., orange movements accomplished by removable elastics, etc.), thattype of movement may occur at a slower rate if patient compliance ispoor. Evaluating the independent progress of various interventions andtooth movements can help guide future treatment decisions for anindividual patient and/or a population of patients.

As previously noted, the residual movement data can characterizedifferences in the actual and planned positions of a patient's teeth,and thereby the movements that should be accomplished for the teeth toreach the planned positions. In some embodiments, it may be beneficialto evaluate the movements that have been accomplished, instead of or inaddition to the portions of the planned movements that have not yet beenaccomplished. Therefore as shown in FIG. 54, the process 5304 cancomprise obtaining actual movement data (process portion 5414)characterizing the actual movements that have occurred. An actualmovement can be defined as the difference between the actual position ofa tooth and the original position of the tooth. To obtain the actualmovement data, the residual movement data can be subtracted from theplanned movement data. Overall actual movement data can be obtained bysubtracting the overall residual movement data from the overall plannedmovement data and/or component actual movement data can be obtained bysubtracting the corresponding component residual movement data from thecorresponding component planned movement data. Additionally oralternatively, the process 5304 shown in FIG. 54 can be performed withthe OTA digital model in place of the FTA digital model to obtain actualmovement data, and the residual movement data can be obtained bysubtracting the actual movement data from the planned movement data.

As previously noted, the process of evaluating an orthodontic treatment5300 includes evaluating the position data and/or the movement data(process portion 5306) obtained via process portion 5304. Processportion 5306 can comprise evaluating the position and/or movement datafor a single tooth, one tooth in one dental arch, multiple teeth in onedental arch, all teeth in one dental arch, one teeth in both dentalarches, multiple teeth in both dental arches, and/or all teeth in bothdental arches. The position and/or movement data can be evaluated alongone translational dimension, two translational dimensions, threetranslational dimensions, one rotational dimension, two rotationaldimensions, and/or three rotational dimensions. In some embodiments,evaluating the position and/or movement data comprises obtaining aperformance parameter, which can comprise a magnitude of a movement, adirection of a movement, a speed of a movement, a percentage of aplanned movement that was accomplished, a percentage of a plannedmovement that has not yet been accomplished, and/or others. For example,a performance parameter can comprise a Euclidian distance between anactual position of a tooth and a planned position of the tooth tocharacterize a magnitude of a 3D translation of the tooth according tothe residual movement data. Additionally or alternatively, a performanceparameter can comprise an axis-angle representation (e.g., a rotationvector, an Euler vector, etc.) to characterize a magnitude and an angleof a 3D rotation of a tooth from an original position to an actualposition according to the actual movement data.

As but one example for a single tooth, the performance parameters cancomprise a completed percentage of a planned overall movement, acompleted percentage of a planned blue movement, and/or a completedpercentage of a planned orange movement. For each overall movement andeach component movement, the performance parameter can characterize themovement along one or more translational directions and/or one or morerotational directions. For example, a completed percentage of a plannedoverall movement can comprise a Euclidean distance between a center ofmass of the tooth in an actual position and the center of mass of thetooth in an original position divided by a Euclidean distance betweenthe center of mass of the tooth in the original position and the centerof mass of the tooth in the planned position.

In various embodiments, evaluating the position and/or movement data(process portion 5306) comprises obtaining a performance parametersummarizing performance parameters of multiple teeth. For example, insome embodiments a performance parameter comprises an average of theactual overall movements of two or more of the patient's teeth dividedby an average of the planned overall movements of corresponding ones ofthe patient's teeth. In various embodiments, it may be useful toevaluate corresponding performance parameters of various teeth. Forexample, a performance parameter can be evaluated and compared acrossall teeth, and the tooth with the worst of the performance parameterscan be used to determine an accuracy, efficiency, etc. of the treatment.

Evaluating the position and/or movement data can comprise comparing theposition and/or movement data to a predetermined threshold. In someembodiments, a measure of the actual movement data relative to theplanned movement data can be evaluated against a completion threshold.For example, if the average actual overall movements of all of the teethdivided by the average planned overall movements of all of the teeth isgreater than the completion threshold, the treatment can be consideredcomplete, and any active orthodontic interventions can be discontinued.Such completion threshold can be, for example about 0.8, about 0.85,about 0.90, about 0.95, about 0.99, no less than 0.8, no less than 0.85,no less than 0.90, no less than 0.95, or no less than 0.99. Additionallyor alternatively, a measure of the residual movement data relative tothe planned movement data can be evaluated against a residual threshold.For example, if a residual overall movement of one of the teeth along amesiodistal direction divided by a planned overall movement of the toothalong the mesiodistal direction is less than the residual threshold, thetreatment can be considered complete, and any active orthodonticinterventions can be discontinued. Such residual threshold can be, forexample about 0.05, about 0.1, about 0.15, about 0.2, about 0.25, nomore than 0.05, no more than 0.1, no more than 0.15, no more than 0.2,or no more than 0.25.

Based on the evaluation of the orthodontic treatment, a human operatorand/or an automated process can determine if and/or how treatment shouldproceed. For example, if, based on the evaluation, it is determined thatthe patient's teeth are at or sufficiently close to their desired, finalpositions, the treatment can be concluded in its entirety. Additionallyor alternatively, as previously noted, in some cases certain plannedcomponent movements may be accomplished at varying rates. If a firstcomponent movement is sufficiently accomplished by a first orthodonticintervention but a second component movement to be accomplished by asecond orthodontic intervention has not been sufficiently completed, thefirst orthodontic intervention can be discontinued while the secondorthodontic intervention continues to be employed to move the patient'steeth. In some embodiments, it may be advantageous to modify anorthodontic treatment and/or intervention prior to its completion. As anexample, if it is determined that a patient's teeth are moving muchslower in response to forces applied by orthodontic elastics thananticipated, it may be beneficial to replace the patient's currentelastics with elastics configured to apply greater forces and therebymove the patient's teeth more quickly to reduce the duration of theorthodontic treatment.

As shown in FIG. 19, based on the evaluation the process 1900 fororthodontically treating a patient can repeat, starting with obtainingmovement data. In this example, and in other examples, the actualmovements accomplished compared to the planned movements may not havesufficiently moved the patient's teeth to the desired, final positionsand additional treatment and/or a new or modified treatment may bedesirable or required. For example, if an appliance has been installedin a patient's mouth for a sufficient duration of time such that thetreatment should be completed, but the patient's teeth are notsufficiently close to the planned, final positions, additional treatmentmay be required and/or desired to move the patient's teeth closer to theplanned, final positions. In these and other embodiments, the evaluationof the position data and/or the movement data can inform the next stepsin planning and implementing further orthodontic treatment. For example,based on the types, magnitudes, and directions of the residualmovements, it may be beneficial to complete the treatment using apolymeric aligner that is quick and inexpensive to fabricate. However,if large and/or difficult movements are still needed to move the teethto their final positions, it may be beneficial to design and manufacturean appliance that is better suited to accomplish such movements (e.g.,appliances 100, 3802, etc. as disclosed herein).

If further treatment is desired and/or needed, the process 1900 canrepeat with obtaining new movement data, obtaining a new treatment plan,communicating the new movement data and/or treatment plan, implementingthe new treatment, and/or evaluating the new treatment. In someembodiments, the ATA digital model can be used as the OTA digital modelwhen obtaining new movement data. Additionally or alternatively, theprevious FTA digital model can be used as the new FTA digital model. Inmany cases, the previous or original FTA will not change after some orall of an original treatment has been implemented, because theoriginally-determined final positions of the teeth will remain thepositions at which the teeth function optionally and are aesthetic. Insome cases, it may be useful to modify the FTA based on specificchallenges that occurred during the previous treatment. Obtaining thenew movement data can comprise decomposing overall movements into one ormore component movements, as described herein.

In some embodiments, it may be advantageous to select and/or modify anorthodontic intervention for accomplishing the new movements of theteeth. For example, if the planned intraarch movements were sufficientlyaccomplished during the previous treatment but the planned interarchmovements were not, it may be preferable to replace an appliance thatwas used to accomplish the intraarch movements with a retainerconfigured to maintain the intraarch relationship of the teeth and tosecure the retainer to orthodontic elastics for further modification ofthe patient's interarch arrangement of the teeth. Additionally oralternatively, if an actual movement of a tooth was significantly lessthan the planned movement, it may be advantageous to design an appliancesuch that the appliance is configured to impart a much greater forceand/or moment to the tooth such that the residual movement of the toothcan be accomplished.

In some embodiments, a shape forming fixture of the present technology(e.g., fixture 1700, fixture 3300, etc.) can be modified based onevaluation of the data. If one or more additional appliances should bemanufactured to further reposition a patient's teeth, it can beadvantageous to modify the shape forming fixture based on the evaluationof the position and/or movement data. As discussed herein, positions ofsecuring members of the shape forming fixture can be based onintermediate positions of the patient's teeth (e.g., positions of thepatient's teeth after blue, intraarch movements, etc.). Thus, positionsof the securing portions of a secondary shape forming fixture can bebased on the actual, intermediate positions of the teeth based on thedecomposition of the actual overall movement. Additionally oralternatively, the positions of the securing portions of the secondaryshape forming fixture can be modified based on the evaluation of thedata. For example, if one of the patient's canine teeth moved muchslower than the other teeth, the canine may be overcorrected to agreater degree. In such example, the position of the securing member ofthe shape forming fixture that corresponds to the problematic canine canbe moved such that an appliance formed with the shape forming fixture isconfigured to move the canine to an overcorrected final position.Additionally or alternatively, securing portions of the secondary shapeforming fixture can be modified based on the evaluation of the actualpositions of the securing members. If a securing member was inaccuratelybonded to a patient's tooth such that the actual position of thesecuring member differs from its intended position, it can be beneficialto modify the position of the securing portion of the fixture to reflectthe actual position of the securing member.

As previously noted, it can be useful for an evaluation of a precedingorthodontic treatment to inform a subsequent orthodontic treatment forthe patient. Additionally or alternatively, evaluation of orthodontictreatment of one or more patient can inform orthodontic treatment ofother future patients. Position data (e.g., original position data,final position data, intermediate position data, actual position data,etc.) and/or movement data (e.g., planned overall movement data, plannedcomponent movement data, actual overall movement data, actual componentmovement data, residual overall movement data, residual componentmovement data, etc.) associated with multiple patients can be stored ina database. Other information such as patient demographic information,clinical information, orthodontic intervention information, etc. can bestored in the database. The data stored in the database can comprisecategorical variables (e.g., sex, age group, ethnicity, type ofintervention, tooth type, jaw, appliance geometric design, etc.) and/orcontinuous variables (e.g., residual overall movement of a tooth,percentage of planned component movements that was completed, force tobe imparted on a tooth by an appliance, speed of tooth movement, etc.).

The data stored in the database can be evaluated to assess relationshipsbetween variables. For example, the data can be statistically analyzedto determine how types of orthodontic interventions are related topercentages of planned component movements that are accomplished, todetermine if and/or how age group of the patient is related to a maximumresidual overall movement after use of a first orthodontic intervention,determine how a force to be imparted to a tooth by an appliance and thetype of tooth is related to movement speed, etc. The statisticalanalysis of the data can comprise a univariate analysis, a bivariateanalysis, or a multivariate analysis. The analysis can comprise aregression (e.g., linear, logarithmic, multiple, etc.), an analysis ofvariance (e.g., ANOVA, MANOVA, etc.), a factor analysis, a clusteranalysis, a discriminant analysis, a conjoint analysis, a canonicalcorrelation analysis, structural equation modeling, multidimensionalscaling, a t-test, a chi-squared test, or another suitable analysis.

A treatment plan of a patient, including movement data, interventionselections, appliance designs, estimated treatment time, etc., can bebased at least in part on an evaluation of data stored in the database.For example, if evaluation of the data inversely correlates age withtooth movement speed, an appliance designed for an older patient may beconfigured to apply greater forces to the patient's teeth than anappliance designed for a younger patient. In one example, if evaluationof the data indicates that teeth moved by an appliance having a specificdesign are associated with lower percentage completion of plannedoverall movements, a design of the appliance can be modified.

FIG. 58 shows a process 5800 for designing an orthodontic treatment planand/or system in accordance with several embodiments of the presenttechnology. The process 5800 can include running a design algorithm todesign one or more aspects of the appliance and/or manufacturingassembly (such as a shape setting fixture). The process 5800 can beconfigured to modify and/or train the algorithm (via machine learning,neural networks, etc.) any time the process 5800 receives ATA data,actual movement data, and/or residual movement data. In someembodiments, the process 5800 comprises obtaining one or more inputs,such as OTA data (5802), FTA data (5804), patient data (5806) (e.g.,age, ethnicity, etc. as described herein), and/or other data. Theprocess 5800 proceeds with running a design algorithm 5808. The designalgorithm 5808 can output an appliance design, a fixture design, an IDBdesign, and/or another treatment system component (5810). Next, the oneor more treatment system components can be manufactured in theirphysical forms (5812). The process 5800 continues with obtaining ATAdata (5814) and performing an accuracy analysis to obtain actualmovement data and/or residual movement data (5816). The ATA data, actualmovement data, and/or residual movement data can then be fed back intothe design algorithm to improve the design of future treatmentcomponents.

CONCLUSION

Although many of the embodiments are described above with respect tosystems, devices, and methods for orthodontic treatment, the technologyis applicable to other applications and/or other approaches. Moreover,other embodiments in addition to those described herein are within thescope of the technology. Additionally, several other embodiments of thetechnology can have different configurations, components, or proceduresthan those described herein. A person of ordinary skill in the art,therefore, will accordingly understand that the technology can haveother embodiments with additional elements, or the technology can haveother embodiments without several of the features shown and describedabove with reference to FIGS. 1A-58.

The descriptions of embodiments of the technology are not intended to beexhaustive or to limit the technology to the precise form disclosedabove. Where the context permits, singular or plural terms may alsoinclude the plural or singular term, respectively. Although specificembodiments of, and examples for, the technology are described above forillustrative purposes, various equivalent modifications are possiblewithin the scope of the technology, as those skilled in the relevant artwill recognize. For example, while steps are presented in a given order,alternative embodiments may perform steps in a different order. Thevarious embodiments described herein may also be combined to providefurther embodiments.

As used herein, the terms “generally,” “substantially,” “about,” andsimilar terms are used as terms of approximation and not as terms ofdegree, and are intended to account for the inherent variations inmeasured or calculated values that would be recognized by those ofordinary skill in the art.

Moreover, unless the word “or” is expressly limited to mean only asingle item exclusive from the other items in reference to a list of twoor more items, then the use of “or” in such a list is to be interpretedas including (a) any single item in the list, (b) all of the items inthe list, or (c) any combination of the items in the list. Additionally,the term “comprising” is used throughout to mean including at least therecited feature(s) such that any greater number of the same featureand/or additional types of other features are not precluded. It willalso be appreciated that specific embodiments have been described hereinfor purposes of illustration, but that various modifications may be madewithout deviating from the technology. Further, while advantagesassociated with certain embodiments of the technology have beendescribed in the context of those embodiments, other embodiments mayalso exhibit such advantages, and not all embodiments need necessarilyexhibit such advantages to fall within the scope of the technology.Accordingly, the disclosure and associated technology can encompassother embodiments not expressly shown or described herein.

1. A method comprising: obtaining first data characterizing originalpositions of a patient's teeth; obtaining second data characterizingplanned positions of the teeth; for each tooth in one jaw of a patient,determining a planned displacement between the corresponding originalposition and the corresponding planned position based on the first andsecond data; for each planned displacement, determining a first portionof the planned displacement unique to the tooth associated with theplanned displacement, and determining a second portion of the planneddisplacement shared by all of the planned displacements; obtaining thirddata characterizing actual positions of the teeth after the teeth havebeen at least partially repositioned by the orthodontic treatment; foreach tooth in the one jaw of the patient, determining a residualdisplacement between the corresponding actual position and thecorresponding planned position based on the second and third data; foreach residual displacement, determining a first portion of the residualdisplacement unique to the tooth associated with the residualdisplacement, and determining a second portion of the residualdisplacement shared by all of the residual displacements; comparing thefirst portion of the residual displacement to the first portion of theplanned displacement and comparing the second portion of the residualdisplacement to the second portion of the planned displacement; based atleast in part on the comparison, indicating if further orthodontictreatment is recommended; and if further orthodontic treatment isrecommended, manufacturing an orthodontic appliance configured toaccomplish at least one of the first portion of the residualdisplacement or the second portion of the residual displacement.
 2. Themethod of claim 1, wherein the indication includes one or more suggestedorthodontic interventions to accomplish one or more portions of theresidual displacements.
 3. The method of claim 1, wherein comparing acorresponding portion of the planned and residual displacementscomprises determining a remaining percentage of the correspondingportion of the planned displacement.
 4. The method of claim 3, whereinfurther orthodontic treatment is recommended if the percentage remainingof the planned displacement for one of the teeth is greater than apredetermined threshold.
 5. The method of claim 1, wherein furtherorthodontic treatment is recommended if a magnitude of the residualdisplacement for one of the teeth is greater than a predeterminedthreshold.
 6. The method of claim 1, further comprising, beforedetermining the residual displacements, registering the third data tothe second data.
 7. The method of claim 3, wherein registering the thirddata to the second data comprises identifying a rigid transformationthat, when applied to the third data, reduces an error parametercharacterizing a difference between the third data and the second data.8. The method of claim 1, further comprising: for each tooth in the onejaw of the patient, determining an actual displacement between thecorresponding original position and the corresponding actual positionbased on the first and third data; for each actual displacement,determining a first portion of the actual displacement unique to thetooth associated with the actual displacement, and determining a secondportion of the actual displacement shared by all of the actualdisplacements. 9-13. (canceled)
 14. A method comprising: obtaining firstdata characterizing original positions of teeth of a patient; obtainingsecond data characterizing final positions of the patient's teeth; basedon the first and second data, determining planned movement datacharacterizing a planned movement of each of the patient's teeth fromthe original position to the final position; decomposing the plannedmovement data into first planned movement data and second plannedmovement data, wherein the first planned movement data characterizes afirst component of the planned movement achievable by a firstorthodontic intervention, and wherein the second planned movement datacharacterizes a second component of the planned movement achievable by asecond orthodontic intervention that is a different type of orthodonticintervention than the first orthodontic intervention; obtaining thirddata characterizing actual positions of the patient's teeth after atleast one of the first orthodontic intervention or the secondorthodontic intervention has been at least partially implemented; basedon first and third data, determining actual movement data characterizingan actual movement of each of the patient's teeth from the originalposition to the actual position; decomposing the actual movement datainto first actual movement data and second actual movement data, whereinthe first actual movement data characterizes a first component of theactual movement achieved by the first orthodontic intervention, andwherein the second actual movement data characterizes a second componentof the actual movement achieved by the second orthodontic intervention;comparing the first actual movement data to the first planned movementdata and comparing the second actual movement data to the second plannedmovement data; based at least in part on the comparison, indicatingwhether further orthodontic treatment is recommended; and if furtherorthodontic treatment is recommended, obtaining an orthodontic applianceconfigured to achieve a residual movement of at least one of thepatient's teeth, the residual movement comprising a difference betweenthe first planned movement and the first actual movement or a differencebetween the second planned movement and the second actual movement. 15.The method of claim 14, wherein comparing the first actual movement datato the first planned movement data comprises determining a percentage ofthe first portion of the planned movement that has been achieved by thefirst orthodontic intervention.
 16. The method of claim 14, whereincomparing the second actual movement data to the second planned movementdata comprises determining a percentage of the second portion of theplanned movement that has been achieved by the second orthodonticintervention.
 17. (canceled)
 18. The method of claim 14, whereinobtaining the third data comprises obtaining image data characterizingthe patient's teeth after at least one of the first orthodonticintervention or the second orthodontic intervention has been at leastpartially implemented.
 19. A method comprising: obtaining an originaltooth arrangement (OTA) digital model characterizing original positionsof a patient's teeth in a jaw of the patient; obtaining a final tootharrangement (FTA) digital model characterizing desired, final positionsof the patient's teeth in the jaw; based on the OTA and FTA digitalmodels, determining planned displacement data characterizing a plannedmovement of each of the patient's teeth from the original position tothe final position, wherein each planned movement has a first portionunique to the tooth associated with the planned movement and a secondportion shared by all of the planned movements; obtaining an actualtooth arrangement (ATA) digital model characterizing actual positions ofthe patient's teeth in the jaw; registering the ATA digital model to theFTA digital model; based on the registered ATA digital model and the FTAdigital model, determining residual movement data characterizing aresidual movement of each of the patient's teeth from the actualposition to the final position, wherein each residual movement has afirst portion unique to the tooth associated with the residual movementand a second portion shared by all of the residual movements; comparingthe first portions of the planned and residual movements and comparingthe second portions of the planned and residual movements; based on thecomparison, indicating whether further orthodontic treatment isrecommended; and if further orthodontic treatment is recommended,manufacturing an orthodontic appliance configured to accomplish at leastone of the first portion of the residual displacement or the secondportion of the residual displacement.
 20. The method of claim 19,wherein at least one of the OTA digital model, the FTA digital model, orthe ATA digital model is segmented and comprises a plurality of distincttooth models.
 21. The method of claim 20, wherein obtaining the ATAdigital model comprises, for each of the teeth in the ATA digital model,positioning a corresponding one of the distinct tooth models from theOTA digital model or the FTA digital model at the corresponding actualposition of the tooth as characterized by the ATA digital model.
 22. Themethod of claim 14, wherein: the first orthodontic interventioncomprises an appliance including a plurality of attachment portions eachconfigured to secure to one of the patient's teeth and a connectorextending between adjacent ones of the attachment portions; and thesecond orthodontic intervention comprises at least one of an elastic, atemporary anchorage device, a platform, or surgery.
 23. The method ofclaim 14, wherein the orthodontic appliance comprises a plurality ofattachment portions each configured to secure to one of the patient'steeth and a connector extending between adjacent ones of the attachmentportions.
 24. The method of claim 14, wherein the first planned movementis unique to the tooth associated with the first planned movement andthe second planned movement is shared by all of the planned movements.25. The method of claim 14, wherein a first duration of treatment duringwhich the first orthodontic intervention is implemented at leastpartially overlaps with a second duration of treatment during which thesecond orthodontic intervention is implemented.